diff --git a/ampersand-state.js b/ampersand-state.js
index 5f587de..35573d1 100644
--- a/ampersand-state.js
+++ b/ampersand-state.js
@@ -114,6 +114,10 @@ _.extend(Base.prototype, BBEvents, {
 
         options = options || {};
 
+        if (options.parse) {
+            attrs = this.parse(attrs, options);
+        }
+
         if (!this._validate(attrs, options)) return false;
 
         // Extract attributes and options.
diff --git a/test/full.js b/test/full.js
index 52c6dd0..05cdc13 100644
--- a/test/full.js
+++ b/test/full.js
@@ -1542,74 +1542,31 @@ test('#68, #110 mixin props should not be deleted', function (t) {
     t.end();
 });
 
-test('#114 setOnce allows values to be set once and only once', function (t) {
-    var Model = State.extend({
-        props: {
-            x: {
-                type: 'string',
-                setOnce: true,
-                required: true,
-            }
-        }
-    });
-
-    var model = new Model({ x: 'foo' });
-
-    t.equal(model.x, 'foo');
-
-    t.throws(function () {
-        model.x = 'bar';
-    }, /can only be set once/);
-
-    t.end();
-});
-
-test('#118 setOnce can be used with default string', function (t) {
-    var TimeRange = State.extend({
-        props: {
-            timezone: {
-                type: 'string',
-                default: 'something that can only be set as the default',
-                setOnce: true
-            }
-        }
-    });
-
-    var tr = new TimeRange();
-
-    t.throws(function () {
-        tr.timezone = 'new thing';
-    }, 'since it has a default, this should throw'); 
-    
-
-    var tr2;
-
-    t.doesNotThrow(function () {
-        tr2 = new TimeRange({timezone: 'my thing'});
-    }, 'if we set on init, should overwrite default');
-    
-    t.throws(function () {
-        tr.timezone = 'new thing';  
-    }, 'should now fail since its been set'); 
-    
-    var OtherTimeRange = State.extend({
+test('#106 #84 - set accepts options.parse', function (t) {
+    var me;
+    var Person = State.extend({
         props: {
-            timezone: {
-                type: 'string',
-                setOnce: true
-            }
+            id: 'number',
+            name: 'string'
+        },
+        parse: function (attrs) {
+            attrs.id = attrs.personID;
+            delete attrs.personID;
+            return attrs;
         }
     });
 
-    tr = new OtherTimeRange();
+    me = new Person();
+    me.set({ personID: 123, name: 'Phil' });
+    t.equal(me.id, undefined, 'does not parse attributes if not passed');
 
-    t.doesNotThrow(function () {
-        tr.timezone = 'thing';
-    }, 'should not throw first time'); 
+    me = new Person();
+    me.set({ personID: 123, name: 'Phil' },{ parse: false });
+    t.equal(me.id, undefined, 'does not parse attributes if options.parse is false');
 
-    t.throws(function () {
-        tr.timezone = 'other thing';
-    }, 'throws second time');
+    me = new Person();
+    me.set({ personID: 123, name: 'Phil' },{ parse: true });
+    t.equal(me.id, 123, 'parses attributes if options.parse is true');
 
     t.end();
 });