diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..7f6e192
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,6 @@
+root = true
+
+[*]
+end_of_line = lf
+insert_final_newline = true
+max_line_length = 140
\ No newline at end of file
diff --git a/build.gradle b/build.gradle
index f964538..d82ca5b 100644
--- a/build.gradle
+++ b/build.gradle
@@ -5,7 +5,7 @@ buildscript {
 
         corda_artifactory_url = 'https://software.r3.com/artifactory'
         corda_group = 'net.corda'
-        corda_release_version = '4.8'
+        corda_release_version = '4.9'
 
         corda_gradle_plugin_group = 'net.corda.plugins'
         corda_gradle_plugin_version = '5.0.4'
@@ -14,10 +14,10 @@ buildscript {
         junit_version = '5.3.1'
 
         onixlabs_group = 'io.onixlabs'
-        onixlabs_corda_core_release_version = '4.0.0-rc3'
-        onixlabs_corda_idfx_release_version = '4.0.0-rc5'
+        onixlabs_corda_core_release_version = '4.0.1'
+        onixlabs_corda_idfx_release_version = '4.0.1'
 
-        cordapp_platform_version = 10
+        cordapp_platform_version = 11
         cordapp_contract_name = 'ONIXLabs Corda BNMS Contract'
         cordapp_workflow_name = 'ONIXLabs Corda BNMS Workflow'
         cordapp_vendor_name = 'ONIXLabs'
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/ConfigurationBuilder.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/ConfigurationBuilder.kt
index da282d3..803bb54 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/ConfigurationBuilder.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/ConfigurationBuilder.kt
@@ -196,7 +196,7 @@ class ConfigurationBuilder(private val settings: MutableSet<Setting<*>>) {
      *
      * @return Returns a configuration containing the settings built by this configuration builder.
      */
-    fun toConfiguration(): Configuration {
+    internal fun toConfiguration(): Configuration {
         return Configuration(settings)
     }
 }
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/Membership.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/Membership.kt
index 4cf35b6..7df2b1a 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/Membership.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/Membership.kt
@@ -92,17 +92,7 @@ data class Membership(
      * @return Returns a persistent state entity.
      */
     override fun generateMappedObject(schema: MappedSchema): PersistentState = when (schema) {
-        is MembershipSchemaV1 -> MembershipEntity(
-            linearId = linearId.id,
-            externalId = linearId.externalId,
-            holder = holder,
-            networkValue = network.value,
-            normalizedNetworkValue = network.normalizedValue,
-            networkOperator = network.operator,
-            networkHash = network.hash.toString(),
-            isNetworkOperator = isNetworkOperator,
-            hash = hash.toString()
-        )
+        is MembershipSchemaV1 -> MembershipEntity(this)
         else -> throw IllegalArgumentException("Unrecognised schema: $schema.")
     }
 
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipAttestation.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipAttestation.kt
index 1abd068..073d814 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipAttestation.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipAttestation.kt
@@ -68,6 +68,19 @@ class MembershipAttestation internal constructor(
     previousStateRef
 ), NetworkState {
 
+    /**
+     * Represents a membership attestation; a proof that a particular [Membership] state has been witnessed.
+     *
+     * @param attestor The party who is attesting to the witnessed [Membership] state.
+     * @param membership The [Membership] state that is being witnessed and attested.
+     * @param status The status of the attestation.
+     * @param metadata Additional information about the attestation.
+     * @param linearId The unique identifier of the attestation.
+     * @param previousStateRef The state reference of the previous state in the chain.
+     *
+     * The primary constructor of the [MembershipAttestation] class is deliberately private
+     * to enforce static attestation pointers via the secondary constructor.
+     */
     constructor(
         attestor: AbstractParty,
         membership: StateAndRef<Membership>,
@@ -79,7 +92,7 @@ class MembershipAttestation internal constructor(
         membership.state.data.network,
         attestor,
         setOf(membership.state.data.holder),
-        membership.toStaticAttestationPointer(identifier = membership.state.data.linearId.toString()),
+        membership.toStaticAttestationPointer(),
         status,
         metadata,
         linearId,
@@ -126,22 +139,7 @@ class MembershipAttestation internal constructor(
      * @return Returns a persistent state entity.
      */
     override fun generateMappedObject(schema: MappedSchema): PersistentState = when (schema) {
-        is MembershipAttestationSchemaV1 -> MembershipAttestationEntity(
-            linearId = linearId.id,
-            externalId = linearId.externalId,
-            attestor = attestor,
-            holder = holder,
-            networkValue = network.value,
-            normalizedNetworkValue = network.normalizedValue,
-            networkOperator = network.operator,
-            networkHash = network.hash.toString(),
-            pointer = pointer.statePointer.toString(),
-            pointerStateType = pointer.stateType.canonicalName,
-            pointerHash = pointer.hash.toString(),
-            status = status,
-            previousStateRef = previousStateRef?.toString(),
-            hash = hash.toString()
-        )
+        is MembershipAttestationSchemaV1 -> MembershipAttestationEntity(this)
         else -> super.generateMappedObject(schema)
     }
 
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipAttestationSchema.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipAttestationSchema.kt
index f5e52a9..34fbbd1 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipAttestationSchema.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipAttestationSchema.kt
@@ -76,5 +76,22 @@ object MembershipAttestationSchema {
 
         @Column(name = "hash", nullable = false, unique = true)
         val hash: String = ""
-    ) : PersistentState()
+    ) : PersistentState() {
+        constructor(attestation: MembershipAttestation) : this(
+            linearId = attestation.linearId.id,
+            externalId = attestation.linearId.externalId,
+            attestor = attestation.attestor,
+            holder = attestation.holder,
+            networkValue = attestation.network.value,
+            normalizedNetworkValue = attestation.network.normalizedValue,
+            networkOperator = attestation.network.operator,
+            networkHash = attestation.network.hash.toString(),
+            pointer = attestation.pointer.statePointer.toString(),
+            pointerStateType = attestation.pointer.stateType.canonicalName,
+            pointerHash = attestation.pointer.hash.toString(),
+            status = attestation.status,
+            previousStateRef = attestation.previousStateRef?.toString(),
+            hash = attestation.hash.toString()
+        )
+    }
 }
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipSchema.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipSchema.kt
index 8fdb4a5..001db0d 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipSchema.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/membership/MembershipSchema.kt
@@ -61,5 +61,17 @@ object MembershipSchema {
 
         @Column(name = "hash", nullable = false, unique = true)
         val hash: String = ""
-    ) : PersistentState()
+    ) : PersistentState() {
+        constructor(membership: Membership) : this(
+            linearId = membership.linearId.id,
+            externalId = membership.linearId.externalId,
+            holder = membership.holder,
+            networkValue = membership.network.value,
+            normalizedNetworkValue = membership.network.normalizedValue,
+            networkOperator = membership.network.operator,
+            networkHash = membership.network.hash.toString(),
+            isNetworkOperator = membership.isNetworkOperator,
+            hash = membership.hash.toString()
+        )
+    }
 }
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/Relationship.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/Relationship.kt
index e675720..e7edba4 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/Relationship.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/Relationship.kt
@@ -94,15 +94,7 @@ data class Relationship(
      * @return Returns a persistent state entity.
      */
     override fun generateMappedObject(schema: MappedSchema): PersistentState = when (schema) {
-        is RelationshipSchemaV1 -> RelationshipEntity(
-            linearId = linearId.id,
-            externalId = linearId.externalId,
-            networkValue = network.value,
-            normalizedNetworkValue = network.normalizedValue,
-            networkOperator = network.operator,
-            networkHash = network.hash.toString(),
-            hash = hash.toString()
-        )
+        is RelationshipSchemaV1 -> RelationshipEntity(this)
         else -> throw IllegalArgumentException("Unrecognised schema: $schema.")
     }
 
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipAttestation.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipAttestation.kt
index 1ce9029..791d673 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipAttestation.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipAttestation.kt
@@ -18,6 +18,7 @@ package io.onixlabs.corda.bnms.contract.relationship
 
 import io.onixlabs.corda.bnms.contract.Network
 import io.onixlabs.corda.bnms.contract.NetworkState
+import io.onixlabs.corda.bnms.contract.membership.Membership
 import io.onixlabs.corda.bnms.contract.relationship.RelationshipAttestationSchema.RelationshipAttestationEntity
 import io.onixlabs.corda.bnms.contract.relationship.RelationshipAttestationSchema.RelationshipAttestationSchemaV1
 import io.onixlabs.corda.identityframework.contract.attestations.Attestation
@@ -32,6 +33,20 @@ import net.corda.core.identity.AbstractParty
 import net.corda.core.schemas.MappedSchema
 import net.corda.core.schemas.PersistentState
 
+/**
+ * Represents a relationship attestation; a proof that a particular [Relationship] state has been witnessed.
+ *
+ * @property network The business network that this relationship attestation belongs to.
+ * @property attestor The party who is attesting to the witnessed [Relationship] state.
+ * @property attestees The parties of this attestation, usually the participants of the attested [Relationship] state.
+ * @property pointer The pointer to the attested [Relationship] state.
+ * @property status The status of the attestation.
+ * @property metadata Additional information about the attestation.
+ * @property linearId The unique identifier of the attestation.
+ * @property previousStateRef The state reference of the previous state in the chain.
+ * @property hash The unique hash which represents this attestation.
+ * @property participants The participants of this attestation; namely the attestor and attestees.
+ */
 @BelongsToContract(RelationshipAttestationContract::class)
 class RelationshipAttestation internal constructor(
     override val network: Network,
@@ -89,21 +104,7 @@ class RelationshipAttestation internal constructor(
     }
 
     override fun generateMappedObject(schema: MappedSchema): PersistentState = when (schema) {
-        is RelationshipAttestationSchemaV1 -> RelationshipAttestationEntity(
-            linearId = linearId.id,
-            externalId = linearId.externalId,
-            attestor = attestor,
-            networkValue = network.value,
-            normalizedNetworkValue = network.normalizedValue,
-            networkOperator = network.operator,
-            networkHash = network.hash.toString(),
-            pointer = pointer.statePointer.toString(),
-            pointerStateType = pointer.stateType.canonicalName,
-            pointerHash = pointer.hash.toString(),
-            status = status,
-            previousStateRef = previousStateRef?.toString(),
-            hash = hash.toString()
-        )
+        is RelationshipAttestationSchemaV1 -> RelationshipAttestationEntity(this)
         else -> super.generateMappedObject(schema)
     }
 
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipAttestationSchema.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipAttestationSchema.kt
index fb1a616..1ecf507 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipAttestationSchema.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipAttestationSchema.kt
@@ -73,5 +73,21 @@ object RelationshipAttestationSchema {
 
         @Column(name = "hash", nullable = false, unique = true)
         val hash: String = ""
-    ) : PersistentState()
+    ) : PersistentState() {
+        constructor(attestation: RelationshipAttestation) : this(
+            linearId = attestation.linearId.id,
+            externalId = attestation.linearId.externalId,
+            attestor = attestation.attestor,
+            networkValue = attestation.network.value,
+            normalizedNetworkValue = attestation.network.normalizedValue,
+            networkOperator = attestation.network.operator,
+            networkHash = attestation.network.hash.toString(),
+            pointer = attestation.pointer.statePointer.toString(),
+            pointerStateType = attestation.pointer.stateType.canonicalName,
+            pointerHash = attestation.pointer.hash.toString(),
+            status = attestation.status,
+            previousStateRef = attestation.previousStateRef?.toString(),
+            hash = attestation.hash.toString()
+        )
+    }
 }
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipConfiguration.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipConfiguration.kt
index 85496e9..f8017e4 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipConfiguration.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipConfiguration.kt
@@ -57,17 +57,7 @@ class RelationshipConfiguration private constructor(
         get() = SecureHash.sha256("${configuration.hash}$relationshipLinearId")
 
     override fun generateMappedObject(schema: MappedSchema) = when (schema) {
-        is RelationshipConfigurationSchemaV1 -> RelationshipConfigurationEntity(
-            linearId = linearId.id,
-            externalId = linearId.externalId,
-            relationshipLinearId = relationshipLinearId.id,
-            relationshipExternalId = relationshipLinearId.externalId,
-            networkValue = network.value,
-            networkOperator = network.operator,
-            networkHash = network.hash.toString(),
-            configurationHash = configuration.hash.toString(),
-            hash = hash.toString()
-        )
+        is RelationshipConfigurationSchemaV1 -> RelationshipConfigurationEntity(this)
         else -> throw IllegalArgumentException("Unrecognised schema: $schema.")
     }
 
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipConfigurationSchema.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipConfigurationSchema.kt
index d4f696c..2f315b0 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipConfigurationSchema.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipConfigurationSchema.kt
@@ -49,6 +49,9 @@ object RelationshipConfigurationSchema {
         @Column(name = "network_value", nullable = false)
         val networkValue: String = "",
 
+        @Column(name = "normalized_network_value", nullable = false)
+        val normalizedNetworkValue: String = "",
+
         @Column(name = "network_operator", nullable = true)
         val networkOperator: AbstractParty? = null,
 
@@ -60,5 +63,18 @@ object RelationshipConfigurationSchema {
 
         @Column(name = "hash", nullable = false)
         val hash: String = ""
-    ) : PersistentState()
+    ) : PersistentState() {
+        constructor(configuration: RelationshipConfiguration) : this(
+            linearId = configuration.linearId.id,
+            externalId = configuration.linearId.externalId,
+            relationshipLinearId = configuration.relationshipLinearId.id,
+            relationshipExternalId = configuration.relationshipLinearId.externalId,
+            networkValue = configuration.network.value,
+            normalizedNetworkValue = configuration.network.normalizedValue,
+            networkOperator = configuration.network.operator,
+            networkHash = configuration.network.hash.toString(),
+            configurationHash = configuration.configuration.hash.toString(),
+            hash = configuration.hash.toString()
+        )
+    }
 }
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipSchema.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipSchema.kt
index 2735d11..f50f8d0 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipSchema.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/relationship/RelationshipSchema.kt
@@ -54,5 +54,15 @@ object RelationshipSchema {
 
         @Column(name = "hash", nullable = false, unique = true)
         val hash: String = ""
-    ) : PersistentState()
+    ) : PersistentState() {
+        constructor(relationship: Relationship) : this(
+            linearId = relationship.linearId.id,
+            externalId = relationship.linearId.externalId,
+            networkValue = relationship.network.value,
+            normalizedNetworkValue = relationship.network.normalizedValue,
+            networkOperator = relationship.network.operator,
+            networkHash = relationship.network.hash.toString(),
+            hash = relationship.hash.toString()
+        )
+    }
 }
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/revocation/RevocationLock.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/revocation/RevocationLock.kt
index 54b3e57..d44689d 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/revocation/RevocationLock.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/revocation/RevocationLock.kt
@@ -40,12 +40,7 @@ data class RevocationLock<T : LinearState>(
     }
 
     override fun generateMappedObject(schema: MappedSchema): PersistentState = when (schema) {
-        is RevocationLockSchemaV1 -> RevocationLockEntity(
-            owner = owner,
-            pointerStateLinearId = pointer.pointer.id,
-            pointerStateExternalId = pointer.pointer.externalId,
-            pointerStateClass = pointer.type.canonicalName
-        )
+        is RevocationLockSchemaV1 -> RevocationLockEntity(this)
         else -> throw IllegalArgumentException("Unrecognised schema: $schema.")
     }
 
diff --git a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/revocation/RevocationLockSchema.kt b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/revocation/RevocationLockSchema.kt
index e3826c6..f3612ac 100644
--- a/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/revocation/RevocationLockSchema.kt
+++ b/onixlabs-corda-bnms-contract/src/main/kotlin/io/onixlabs/corda/bnms/contract/revocation/RevocationLockSchema.kt
@@ -46,5 +46,12 @@ object RevocationLockSchema {
 
         @Column(name = "pointer_state_class", nullable = false)
         val pointerStateClass: String = ""
-    ) : PersistentState()
-}
\ No newline at end of file
+    ) : PersistentState() {
+        constructor(revocationLock: RevocationLock<*>) : this(
+            owner = revocationLock.owner,
+            pointerStateLinearId = revocationLock.pointer.pointer.id,
+            pointerStateExternalId = revocationLock.pointer.pointer.externalId,
+            pointerStateClass = revocationLock.pointer.type.canonicalName
+        )
+    }
+}
diff --git a/onixlabs-corda-bnms-contract/src/main/resources/migration/relationship-configuration-schema.changelog-v1.xml b/onixlabs-corda-bnms-contract/src/main/resources/migration/relationship-configuration-schema.changelog-v1.xml
index 4bf0c7f..3a0b79a 100644
--- a/onixlabs-corda-bnms-contract/src/main/resources/migration/relationship-configuration-schema.changelog-v1.xml
+++ b/onixlabs-corda-bnms-contract/src/main/resources/migration/relationship-configuration-schema.changelog-v1.xml
@@ -21,6 +21,9 @@
             <column name="network_value" type="nvarchar(255)">
                 <constraints nullable="false"/>
             </column>
+            <column name="normalized_network_value" type="nvarchar(255)">
+                <constraints nullable="false"/>
+            </column>
             <column name="network_operator" type="nvarchar(255)"/>
             <column name="network_hash" type="nvarchar(64)">
                 <constraints nullable="false"/>
@@ -36,4 +39,4 @@
                        constraintName="PK_relationship_configuration_states"
                        tableName="relationship_configuration_states"/>
     </changeSet>
-</databaseChangeLog>
\ No newline at end of file
+</databaseChangeLog>
diff --git a/onixlabs-corda-bnms-contract/src/test/kotlin/io/onixlabs/corda/bnms/contract/ContractTest.kt b/onixlabs-corda-bnms-contract/src/test/kotlin/io/onixlabs/corda/bnms/contract/ContractTest.kt
index cb8f6f5..be4dbf9 100644
--- a/onixlabs-corda-bnms-contract/src/test/kotlin/io/onixlabs/corda/bnms/contract/ContractTest.kt
+++ b/onixlabs-corda-bnms-contract/src/test/kotlin/io/onixlabs/corda/bnms/contract/ContractTest.kt
@@ -55,7 +55,7 @@ abstract class ContractTest {
     @BeforeEach
     private fun setup() {
         val networkParameters = testNetworkParameters(
-            minimumPlatformVersion = 5,
+            minimumPlatformVersion = 11,
             notaries = listOf(NotaryInfo(TestIdentity(DUMMY_NOTARY_NAME, 20).party, true))
         )
         _services = MockServices(cordapps, IDENTITY_A, networkParameters, IDENTITY_B, IDENTITY_C)
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.FlowLogic.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.FlowLogic.kt
index 259eb96..defeaa0 100644
--- a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.FlowLogic.kt
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.FlowLogic.kt
@@ -19,14 +19,10 @@ package io.onixlabs.corda.bnms.workflow
 import co.paralleluniverse.fibers.Suspendable
 import io.onixlabs.corda.bnms.contract.membership.Membership
 import io.onixlabs.corda.bnms.contract.membership.MembershipAttestation
-import io.onixlabs.corda.bnms.contract.membership.MembershipAttestationSchema.MembershipAttestationEntity
-import io.onixlabs.corda.bnms.contract.membership.MembershipSchema.MembershipEntity
 import io.onixlabs.corda.bnms.contract.relationship.Relationship
 import io.onixlabs.corda.bnms.contract.relationship.RelationshipAttestation
 import io.onixlabs.corda.bnms.contract.revocation.RevocationLock
-import io.onixlabs.corda.bnms.contract.revocation.RevocationLockSchema.RevocationLockEntity
 import io.onixlabs.corda.core.services.any
-import io.onixlabs.corda.core.services.equalTo
 import io.onixlabs.corda.core.services.singleOrNull
 import io.onixlabs.corda.core.services.vaultServiceFor
 import io.onixlabs.corda.core.workflow.currentStep
@@ -54,18 +50,43 @@ fun FlowLogic<*>.checkMembershipHandler(session: FlowSession): Boolean {
 
 @Suspendable
 fun FlowLogic<*>.checkMembershipExists(membership: Membership) {
-    val membershipExists = serviceHub.vaultServiceFor<Membership>().any {
+    val existingMembership = serviceHub.vaultServiceFor<Membership>().singleOrNull {
         stateStatus(Vault.StateStatus.ALL)
-        expression(MembershipEntity::hash equalTo membership.hash.toString())
+        membershipHash(membership.hash)
     }
 
-    if (membershipExists) {
-        throw FlowException("Membership state with the specified unique hash already exists: ${membership.hash}.")
+    if (existingMembership != null) {
+        throw FlowException("The specified membership already exists: ${existingMembership.state.data}.")
     }
 }
 
 @Suspendable
-fun FlowLogic<*>.checkMembershipsAndAttestations(relationship: Relationship) {
+fun FlowLogic<*>.checkMembershipAttestationExistsForIssuance(attestation: MembershipAttestation) {
+    val existingAttestation = serviceHub.vaultServiceFor<MembershipAttestation>().singleOrNull {
+        membershipAttestationAttestor(attestation.attestor)
+        membershipAttestationHolder(attestation.holder)
+        membershipAttestationNetworkHash(attestation.network.hash)
+    }
+
+    if (existingAttestation != null) {
+        throw FlowException("The specified membership attestation already exists and should be amended: ${existingAttestation.state.data}.")
+    }
+}
+
+@Suspendable
+fun FlowLogic<*>.checkMembershipAttestationExistsForAmendment(attestation: MembershipAttestation) {
+    val existingAttestation = serviceHub.vaultServiceFor<MembershipAttestation>().singleOrNull {
+        stateStatus(Vault.StateStatus.ALL)
+        membershipAttestationHash(attestation.hash)
+    }
+
+    if (existingAttestation != null) {
+        throw FlowException("The specified membership attestation already exists: ${existingAttestation.state.data}.")
+    }
+}
+
+@Suspendable
+fun FlowLogic<*>.checkMembershipsAndAttestations(relationship: Relationship, ourAttestorIdentity: AbstractParty = ourIdentity) {
     currentStep(CheckMembershipStep)
     val counterparties = relationship.participants
         .map { serviceHub.identityService.requireWellKnownPartyFromAnonymous(it) }
@@ -73,19 +94,22 @@ fun FlowLogic<*>.checkMembershipsAndAttestations(relationship: Relationship) {
 
     counterparties.forEach {
         val membership = serviceHub.vaultServiceFor<Membership>().singleOrNull {
-            expression(MembershipEntity::holder equalTo it)
-            expression(MembershipEntity::networkHash equalTo relationship.network.hash.toString())
+            membershipHolder(it)
+            membershipNetworkHash(relationship.network.hash)
         } ?: throw FlowException(buildString {
-            append("Membership for '$it' on network '${relationship.network}' ")
-            append("could not be found, or has not been witnessed by this node.")
+            append("Membership with the specified details could not be found, or has not been witnessed by this node: ")
+            append("Holder = $it, ")
+            append("Network = ${relationship.network}.")
         })
 
         serviceHub.vaultServiceFor<MembershipAttestation>().singleOrNull {
-            expression(MembershipAttestationEntity::attestor equalTo ourIdentity)
-            expression(MembershipAttestationEntity::pointer equalTo membership.ref.toString())
+            membershipAttestationAttestor(ourAttestorIdentity)
+            membershipAttestationPointer(membership.ref)
         } ?: throw FlowException(buildString {
-            append("MembershipAttestation for '${membership.state.data.holder}' ")
-            append("could not be found, or has not been witnessed by this node.")
+            append("Membership attestation with the specified details could not be found, or has not been witnessed by this node: ")
+            append("Holder = ${membership.state.data.holder}, ")
+            append("Attestor = $ourAttestorIdentity, ")
+            append("Network = ${membership.state.data.network}.")
         })
     }
 }
@@ -93,9 +117,9 @@ fun FlowLogic<*>.checkMembershipsAndAttestations(relationship: Relationship) {
 @Suspendable
 fun FlowLogic<*>.checkRevocationLockExists(owner: AbstractParty, state: LinearState) {
     val revocationLockExists = serviceHub.vaultServiceFor<RevocationLock<*>>().any {
-        expression(RevocationLockEntity::owner equalTo owner)
-        expression(RevocationLockEntity::pointerStateClass equalTo state.javaClass.canonicalName)
-        expression(RevocationLockEntity::pointerStateLinearId equalTo state.linearId.id)
+        revocationLockOwner(owner)
+        revocationLockPointerStateClass(state.javaClass)
+        revocationLockPointerStateLinearId(state.linearId.id)
     }
 
     if (revocationLockExists) {
@@ -105,14 +129,17 @@ fun FlowLogic<*>.checkRevocationLockExists(owner: AbstractParty, state: LinearSt
 
 @Suspendable
 fun FlowLogic<*>.findMembershipForAttestation(attestation: MembershipAttestation): StateAndRef<Membership> {
-    return attestation.pointer.resolve(serviceHub) ?: throw FlowException(
-        "Membership for the specified attestation could not be found, or has not been witnessed by this node."
-    )
+    return attestation.pointer.resolve(serviceHub) ?: throw FlowException(buildString {
+        append("Membership with the specified details could not be found, or has not been witnessed by this node: ")
+        append("Holder = ${attestation.holder}, ")
+        append("Network = ${attestation.network}.")
+    })
 }
 
 @Suspendable
 fun FlowLogic<*>.findRelationshipForAttestation(attestation: RelationshipAttestation): StateAndRef<Relationship> {
-    return attestation.pointer.resolve(serviceHub) ?: throw FlowException(
-        "Relationship for the specified attestation could not be found, or has not been witnessed by this node."
-    )
+    return attestation.pointer.resolve(serviceHub) ?: throw FlowException(buildString {
+        append("Relationship with the specified details could not be found, or has not been witnessed by this node: ")
+        append("Network = ${attestation.network}.")
+    })
 }
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.Membership.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.Membership.kt
new file mode 100644
index 0000000..0acae10
--- /dev/null
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.Membership.kt
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2020-2022 ONIXLabs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.onixlabs.corda.bnms.workflow
+
+import io.onixlabs.corda.bnms.contract.membership.Membership
+import io.onixlabs.corda.bnms.contract.membership.MembershipSchema.MembershipEntity
+import io.onixlabs.corda.core.services.QueryDsl
+import io.onixlabs.corda.core.services.QueryDslContext
+import io.onixlabs.corda.core.services.equalTo
+import io.onixlabs.corda.core.services.isNull
+import net.corda.core.crypto.SecureHash
+import net.corda.core.identity.AbstractParty
+
+@QueryDslContext
+fun QueryDsl<Membership>.membershipHolder(value: AbstractParty) {
+    expression(MembershipEntity::holder equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<Membership>.membershipNetworkValue(value: String) {
+    expression(MembershipEntity::networkValue equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<Membership>.membershipNormalizedNetworkValue(value: String) {
+    expression(MembershipEntity::normalizedNetworkValue equalTo value.toUpperCase())
+}
+
+@QueryDslContext
+fun QueryDsl<Membership>.membershipNetworkOperator(value: AbstractParty?) {
+    if (value == null) expression(MembershipEntity::networkOperator.isNull())
+    else expression(MembershipEntity::networkOperator equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<Membership>.membershipNetworkHash(value: SecureHash) {
+    expression(MembershipEntity::networkHash equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<Membership>.membershipIsNetworkOperator(value: Boolean) {
+    expression(MembershipEntity::isNetworkOperator equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<Membership>.membershipHash(value: SecureHash) {
+    expression(MembershipEntity::hash equalTo value.toString())
+}
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.MembershipAttestation.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.MembershipAttestation.kt
new file mode 100644
index 0000000..968f03f
--- /dev/null
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.MembershipAttestation.kt
@@ -0,0 +1,91 @@
+/*
+ * Copyright 2020-2022 ONIXLabs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.onixlabs.corda.bnms.workflow
+
+import io.onixlabs.corda.bnms.contract.membership.MembershipAttestation
+import io.onixlabs.corda.bnms.contract.membership.MembershipAttestationSchema.MembershipAttestationEntity
+import io.onixlabs.corda.core.services.QueryDsl
+import io.onixlabs.corda.core.services.QueryDslContext
+import io.onixlabs.corda.core.services.equalTo
+import io.onixlabs.corda.core.services.isNull
+import io.onixlabs.corda.identityframework.contract.attestations.AttestationStatus
+import net.corda.core.contracts.ContractState
+import net.corda.core.contracts.StateRef
+import net.corda.core.crypto.SecureHash
+import net.corda.core.identity.AbstractParty
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationAttestor(value: AbstractParty) {
+    expression(MembershipAttestationEntity::attestor equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationHolder(value: AbstractParty) {
+    expression(MembershipAttestationEntity::holder equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationNetworkValue(value: String) {
+    expression(MembershipAttestationEntity::networkValue equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationNormalizedNetworkValue(value: String) {
+    expression(MembershipAttestationEntity::normalizedNetworkValue equalTo value.toUpperCase())
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationNetworkOperator(value: AbstractParty?) {
+    if (value == null) expression(MembershipAttestationEntity::networkOperator.isNull())
+    else expression(MembershipAttestationEntity::networkOperator equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationNetworkHash(value: SecureHash) {
+    expression(MembershipAttestationEntity::networkHash equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationPointer(value: Any) {
+    expression(MembershipAttestationEntity::pointer equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationPointerStateType(value: Class<out ContractState>) {
+    expression(MembershipAttestationEntity::pointerStateType equalTo value.canonicalName)
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationPointerHash(value: SecureHash) {
+    expression(MembershipAttestationEntity::pointerHash equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationStatus(value: AttestationStatus) {
+    expression(MembershipAttestationEntity::status equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationPreviousStateRef(value: StateRef?) {
+    if (value == null) expression(MembershipAttestationEntity::previousStateRef.isNull())
+    else expression(MembershipAttestationEntity::previousStateRef equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<MembershipAttestation>.membershipAttestationHash(value: SecureHash) {
+    expression(MembershipAttestationEntity::hash equalTo value.toString())
+}
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.Relationship.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.Relationship.kt
new file mode 100644
index 0000000..b4cfa43
--- /dev/null
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.Relationship.kt
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2020-2022 ONIXLabs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.onixlabs.corda.bnms.workflow
+
+import io.onixlabs.corda.bnms.contract.membership.Membership
+import io.onixlabs.corda.bnms.contract.membership.MembershipAttestation
+import io.onixlabs.corda.bnms.contract.membership.MembershipAttestationSchema
+import io.onixlabs.corda.bnms.contract.relationship.Relationship
+import io.onixlabs.corda.bnms.contract.relationship.RelationshipSchema.RelationshipEntity
+import io.onixlabs.corda.core.services.QueryDsl
+import io.onixlabs.corda.core.services.QueryDslContext
+import io.onixlabs.corda.core.services.equalTo
+import io.onixlabs.corda.core.services.isNull
+import io.onixlabs.corda.identityframework.contract.attestations.AttestationStatus
+import net.corda.core.contracts.ContractState
+import net.corda.core.contracts.StateRef
+import net.corda.core.crypto.SecureHash
+import net.corda.core.identity.AbstractParty
+
+@QueryDslContext
+fun QueryDsl<Relationship>.relationshipNetworkValue(value: String) {
+    expression(RelationshipEntity::networkValue equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<Relationship>.relationshipNormalizedNetworkValue(value: String) {
+    expression(RelationshipEntity::normalizedNetworkValue equalTo value.toUpperCase())
+}
+
+@QueryDslContext
+fun QueryDsl<Relationship>.relationshipNetworkOperator(value: AbstractParty?) {
+    if (value == null) expression(RelationshipEntity::networkOperator.isNull())
+    else expression(RelationshipEntity::networkOperator equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<Relationship>.relationshipNetworkHash(value: SecureHash) {
+    expression(RelationshipEntity::networkHash equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<Relationship>.relationshipHash(value: SecureHash) {
+    expression(RelationshipEntity::hash equalTo value.toString())
+}
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RelationshipAttestation.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RelationshipAttestation.kt
new file mode 100644
index 0000000..25e23a1
--- /dev/null
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RelationshipAttestation.kt
@@ -0,0 +1,86 @@
+/*
+ * Copyright 2020-2022 ONIXLabs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.onixlabs.corda.bnms.workflow
+
+import io.onixlabs.corda.bnms.contract.relationship.RelationshipAttestation
+import io.onixlabs.corda.bnms.contract.relationship.RelationshipAttestationSchema.RelationshipAttestationEntity
+import io.onixlabs.corda.core.services.QueryDsl
+import io.onixlabs.corda.core.services.QueryDslContext
+import io.onixlabs.corda.core.services.equalTo
+import io.onixlabs.corda.core.services.isNull
+import io.onixlabs.corda.identityframework.contract.attestations.AttestationStatus
+import net.corda.core.contracts.ContractState
+import net.corda.core.contracts.StateRef
+import net.corda.core.crypto.SecureHash
+import net.corda.core.identity.AbstractParty
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationAttestor(value: AbstractParty) {
+    expression(RelationshipAttestationEntity::attestor equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationNetworkValue(value: String) {
+    expression(RelationshipAttestationEntity::networkValue equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationNormalizedNetworkValue(value: String) {
+    expression(RelationshipAttestationEntity::normalizedNetworkValue equalTo value.toUpperCase())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationNetworkOperator(value: AbstractParty?) {
+    if (value == null) expression(RelationshipAttestationEntity::networkOperator.isNull())
+    else expression(RelationshipAttestationEntity::networkOperator equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationNetworkHash(value: SecureHash) {
+    expression(RelationshipAttestationEntity::networkHash equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationPointer(value: Any) {
+    expression(RelationshipAttestationEntity::pointer equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationPointerStateType(value: Class<out ContractState>) {
+    expression(RelationshipAttestationEntity::pointerStateType equalTo value.canonicalName)
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationPointerHash(value: SecureHash) {
+    expression(RelationshipAttestationEntity::pointerHash equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationStatus(value: AttestationStatus) {
+    expression(RelationshipAttestationEntity::status equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationPreviousStateRef(value: StateRef?) {
+    if (value == null) expression(RelationshipAttestationEntity::previousStateRef.isNull())
+    else expression(RelationshipAttestationEntity::previousStateRef equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipAttestation>.relationshipAttestationHash(value: SecureHash) {
+    expression(RelationshipAttestationEntity::hash equalTo value.toString())
+}
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RelationshipConfiguration.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RelationshipConfiguration.kt
new file mode 100644
index 0000000..7bee87a
--- /dev/null
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RelationshipConfiguration.kt
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2020-2022 ONIXLabs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.onixlabs.corda.bnms.workflow
+
+import io.onixlabs.corda.bnms.contract.relationship.RelationshipConfiguration
+import io.onixlabs.corda.bnms.contract.relationship.RelationshipConfigurationSchema.RelationshipConfigurationEntity
+import io.onixlabs.corda.core.services.QueryDsl
+import io.onixlabs.corda.core.services.QueryDslContext
+import io.onixlabs.corda.core.services.equalTo
+import io.onixlabs.corda.core.services.isNull
+import net.corda.core.crypto.SecureHash
+import net.corda.core.identity.AbstractParty
+import java.util.*
+
+@QueryDslContext
+fun QueryDsl<RelationshipConfiguration>.relationshipConfigurationRelationshipLinearId(value: UUID) {
+    expression(RelationshipConfigurationEntity::relationshipLinearId equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipConfiguration>.relationshipConfigurationRelationshipExternalId(value: String?) {
+    if (value == null) expression(RelationshipConfigurationEntity::relationshipExternalId.isNull())
+    else expression(RelationshipConfigurationEntity::relationshipExternalId equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipConfiguration>.relationshipConfigurationNetworkValue(value: String) {
+    expression(RelationshipConfigurationEntity::networkValue equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipConfiguration>.relationshipConfigurationNormalizedNetworkValue(value: String) {
+    expression(RelationshipConfigurationEntity::normalizedNetworkValue equalTo value.toUpperCase())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipConfiguration>.relationshipConfigurationNetworkOperator(value: AbstractParty?) {
+    if (value == null) expression(RelationshipConfigurationEntity::networkOperator.isNull())
+    else expression(RelationshipConfigurationEntity::networkOperator equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipConfiguration>.relationshipConfigurationNormalizedNetworkHash(value: SecureHash) {
+    expression(RelationshipConfigurationEntity::networkHash equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipConfiguration>.relationshipConfigurationConfigurationHash(value: SecureHash) {
+    expression(RelationshipConfigurationEntity::configurationHash equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RelationshipConfiguration>.relationshipConfigurationHash(value: SecureHash) {
+    expression(RelationshipConfigurationEntity::hash equalTo value.toString())
+}
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RevocationLock.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RevocationLock.kt
new file mode 100644
index 0000000..958b87e
--- /dev/null
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/Extensions.QueryDsl.RevocationLock.kt
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2020-2022 ONIXLabs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.onixlabs.corda.bnms.workflow
+
+import io.onixlabs.corda.bnms.contract.revocation.RevocationLock
+import io.onixlabs.corda.bnms.contract.revocation.RevocationLockSchema.RevocationLockEntity
+import io.onixlabs.corda.core.services.QueryDsl
+import io.onixlabs.corda.core.services.QueryDslContext
+import io.onixlabs.corda.core.services.equalTo
+import io.onixlabs.corda.core.services.isNull
+import net.corda.core.contracts.LinearState
+import net.corda.core.identity.AbstractParty
+import java.util.*
+
+@QueryDslContext
+fun QueryDsl<RevocationLock<*>>.revocationLockOwner(value: AbstractParty) {
+    expression(RevocationLockEntity::owner equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<RevocationLock<*>>.revocationLockPointerStateLinearId(value: UUID) {
+    expression(RevocationLockEntity::pointerStateLinearId equalTo value)
+}
+
+@QueryDslContext
+fun QueryDsl<RevocationLock<*>>.pointerStateExternalId(value: String?) {
+    if (value == null) expression(RevocationLockEntity::pointerStateExternalId.isNull())
+    else expression(RevocationLockEntity::pointerStateExternalId equalTo value.toString())
+}
+
+@QueryDslContext
+fun QueryDsl<RevocationLock<*>>.revocationLockPointerStateClass(value: Class<out LinearState>) {
+    expression(RevocationLockEntity::pointerStateClass equalTo value.canonicalName)
+}
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/membership/AmendMembershipAttestationFlow.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/membership/AmendMembershipAttestationFlow.kt
index 37df9e3..0760e59 100644
--- a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/membership/AmendMembershipAttestationFlow.kt
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/membership/AmendMembershipAttestationFlow.kt
@@ -19,6 +19,7 @@ package io.onixlabs.corda.bnms.workflow.membership
 import co.paralleluniverse.fibers.Suspendable
 import io.onixlabs.corda.bnms.contract.membership.MembershipAttestation
 import io.onixlabs.corda.bnms.workflow.addAmendedMembershipAttestation
+import io.onixlabs.corda.bnms.workflow.checkMembershipAttestationExistsForAmendment
 import io.onixlabs.corda.bnms.workflow.findMembershipForAttestation
 import io.onixlabs.corda.core.workflow.*
 import io.onixlabs.corda.identityframework.workflow.checkAttestationExistsForAmendment
@@ -54,7 +55,7 @@ class AmendMembershipAttestationFlow(
     override fun call(): SignedTransaction {
         currentStep(InitializeFlowStep)
         checkSufficientSessionsForContractStates(sessions, newAttestation)
-        checkAttestationExistsForAmendment(newAttestation)
+        checkMembershipAttestationExistsForAmendment(newAttestation)
 
         val membership = findMembershipForAttestation(newAttestation).referenced()
 
diff --git a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/membership/IssueMembershipAttestationFlow.kt b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/membership/IssueMembershipAttestationFlow.kt
index 1d43271..b0f679f 100644
--- a/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/membership/IssueMembershipAttestationFlow.kt
+++ b/onixlabs-corda-bnms-workflow/src/main/kotlin/io/onixlabs/corda/bnms/workflow/membership/IssueMembershipAttestationFlow.kt
@@ -19,6 +19,8 @@ package io.onixlabs.corda.bnms.workflow.membership
 import co.paralleluniverse.fibers.Suspendable
 import io.onixlabs.corda.bnms.contract.membership.MembershipAttestation
 import io.onixlabs.corda.bnms.workflow.addIssuedMembershipAttestation
+import io.onixlabs.corda.bnms.workflow.checkMembershipAttestationExistsForAmendment
+import io.onixlabs.corda.bnms.workflow.checkMembershipAttestationExistsForIssuance
 import io.onixlabs.corda.bnms.workflow.findMembershipForAttestation
 import io.onixlabs.corda.core.workflow.*
 import io.onixlabs.corda.identityframework.workflow.checkAttestationExistsForIssuance
@@ -53,7 +55,7 @@ class IssueMembershipAttestationFlow(
     override fun call(): SignedTransaction {
         currentStep(InitializeFlowStep)
         checkSufficientSessionsForContractStates(sessions, attestation)
-        checkAttestationExistsForIssuance(attestation)
+        checkMembershipAttestationExistsForIssuance(attestation)
 
         val membership = findMembershipForAttestation(attestation).referenced()
 
diff --git a/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/FlowTest.kt b/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/FlowTest.kt
index c33769d..df11639 100644
--- a/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/FlowTest.kt
+++ b/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/FlowTest.kt
@@ -79,7 +79,7 @@ abstract class FlowTest {
     private fun setup() {
         _network = MockNetwork(
             MockNetworkParameters(
-                networkParameters = testNetworkParameters(minimumPlatformVersion = 10),
+                networkParameters = testNetworkParameters(minimumPlatformVersion = 11),
                 cordappsForAllNodes = listOf(
                     TestCordapp.findCordapp("io.onixlabs.corda.identityframework.contract"),
                     TestCordapp.findCordapp("io.onixlabs.corda.identityframework.workflow"),
diff --git a/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/membership/AmendDuplicateMembershipAttestationFlowTests.kt b/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/membership/AmendDuplicateMembershipAttestationFlowTests.kt
new file mode 100644
index 0000000..798e014
--- /dev/null
+++ b/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/membership/AmendDuplicateMembershipAttestationFlowTests.kt
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2020-2022 ONIXLabs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.onixlabs.corda.bnms.workflow.membership
+
+import io.onixlabs.corda.bnms.contract.membership.Membership
+import io.onixlabs.corda.bnms.contract.membership.MembershipAttestation
+import io.onixlabs.corda.bnms.contract.membership.accept
+import io.onixlabs.corda.bnms.workflow.FlowTest
+import io.onixlabs.corda.bnms.workflow.Pipeline
+import net.corda.core.contracts.StateAndRef
+import net.corda.core.flows.FlowException
+import net.corda.core.transactions.SignedTransaction
+import org.junit.jupiter.api.Test
+import kotlin.test.assertFailsWith
+
+class AmendDuplicateMembershipAttestationFlowTests : FlowTest() {
+
+    private lateinit var membership: StateAndRef<Membership>
+    private lateinit var oldAttestation: StateAndRef<MembershipAttestation>
+    private lateinit var newAttestation: MembershipAttestation
+    private lateinit var transaction: SignedTransaction
+
+    override fun initialize() {
+        Pipeline
+            .create(network)
+            .run(nodeA) {
+                IssueMembershipFlow.Initiator(MEMBERSHIP, observers = setOf(partyB))
+            }
+            .run(nodeB) {
+                membership = it.tx.outRefsOfType<Membership>().single()
+                val attestation = membership.accept(partyB)
+                IssueMembershipAttestationFlow.Initiator(attestation)
+            }
+            .finally {
+                oldAttestation = it.tx.outRefsOfType<MembershipAttestation>().single()
+                transaction = it
+            }
+    }
+
+    @Test
+    fun `AmendMembershipAttestationFlow should fail because an existing membership attestation already exists`() {
+        val exception = assertFailsWith<FlowException> {
+            Pipeline
+                .create(network)
+                .run(nodeB) {
+                    newAttestation = oldAttestation.state.data
+                    AmendMembershipAttestationFlow.Initiator(oldAttestation, newAttestation)
+                }
+        }
+
+        assert(exception.message!!.startsWith("The specified membership attestation already exists:"))
+    }
+}
diff --git a/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/membership/IssueDuplicateMembershipAttestationFlowTests.kt b/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/membership/IssueDuplicateMembershipAttestationFlowTests.kt
new file mode 100644
index 0000000..55d153e
--- /dev/null
+++ b/onixlabs-corda-bnms-workflow/src/test/kotlin/io/onixlabs/corda/bnms/workflow/membership/IssueDuplicateMembershipAttestationFlowTests.kt
@@ -0,0 +1,71 @@
+/*
+ * Copyright 2020-2022 ONIXLabs
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.onixlabs.corda.bnms.workflow.membership
+
+import io.onixlabs.corda.bnms.contract.membership.Membership
+import io.onixlabs.corda.bnms.contract.membership.accept
+import io.onixlabs.corda.bnms.contract.membership.getNextOutput
+import io.onixlabs.corda.bnms.workflow.FlowTest
+import io.onixlabs.corda.bnms.workflow.Pipeline
+import net.corda.core.contracts.StateAndRef
+import net.corda.core.flows.FlowException
+import net.corda.core.transactions.SignedTransaction
+import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
+
+class IssueDuplicateMembershipAttestationFlowTests : FlowTest() {
+
+    private lateinit var oldMembership: StateAndRef<Membership>
+    private lateinit var newMembership: StateAndRef<Membership>
+    private lateinit var transaction: SignedTransaction
+
+    override fun initialize() {
+        Pipeline
+            .create(network)
+            .run(nodeA) {
+                IssueMembershipFlow.Initiator(MEMBERSHIP, observers = setOf(partyB))
+            }
+            .run(nodeB) {
+                oldMembership = it.tx.outRefsOfType<Membership>().single()
+                val attestation = oldMembership.accept(partyB)
+                IssueMembershipAttestationFlow.Initiator(attestation)
+            }
+            .run(nodeA) {
+                val membership = oldMembership.getNextOutput().configure { addSetting("Test", "Test") }
+                AmendMembershipFlow.Initiator(oldMembership, membership, observers = setOf(partyB))
+            }
+            .finally {
+                newMembership = it.tx.outRefsOfType<Membership>().single()
+                transaction = it
+            }
+    }
+
+    @Test
+    fun `IssueMembershipAttestationFlow should fail because an existing membership attestation already exists`() {
+        val exception = assertFailsWith<FlowException> {
+            Pipeline
+                .create(network)
+                .run(nodeB) {
+                    val attestation = newMembership.accept(partyB)
+                    IssueMembershipAttestationFlow.Initiator(attestation)
+                }
+        }
+
+        assert(exception.message!!.startsWith("The specified membership attestation already exists and should be amended:"))
+    }
+}