diff --git a/R/aliases.R b/R/aliases.R
index 04b917a..a75ec94 100644
--- a/R/aliases.R
+++ b/R/aliases.R
@@ -3,63 +3,98 @@
 #' @description List, create, update, and delete function aliases
 #' @template name
 #' @param alias A character string specifying a function alias
-#' @param description Optionally, a max 256-character description of the function for your own use.
+#' @param description Optionally, a max 256-character description of the
+#'   function for your own use.
 #' @param version A character string specifying a function version
 #' @param marker A pagination marker from a previous request.
 #' @param n An integer specifying the number of results to return.
 #' @template dots
 #' @return An object of class \dQuote{aws_lambda_function}.
-#' @details \code{list_functions} lists all functions. \code{get_function} retrieves a specific function and \code{get_function_versions} retrieves all versions of that function. \code{get_function_configuration} returns the configuration details used when creating or updating the function. \code{delete_function} deletes a function, if you have permission to do so.
+#' @details \code{list_functions} lists all functions. \code{get_function}
+#'   retrieves a specific function and \code{get_function_versions} retrieves
+#'   all versions of that function. \code{get_function_configuration} returns
+#'   the configuration details used when creating or updating the function.
+#'   \code{delete_function} deletes a function, if you have permission to do so.
 #' @references
-#'  \href{http://docs.aws.amazon.com/lambda/latest/dg/API_GetAlias.html}{API Reference: GetAlias}
-#'  \href{http://docs.aws.amazon.com/lambda/latest/dg/API_CreateAlias.html}{API Reference: CreateAlias}
-#'  \href{http://docs.aws.amazon.com/lambda/latest/dg/API_UpdateAlias.html}{API Reference: UpdateAlias}
-#'  \href{http://docs.aws.amazon.com/lambda/latest/dg/API_DeleteAlias.html}{API Reference: DeleteAlias}
-#'  \href{http://docs.aws.amazon.com/lambda/latest/dg/API_ListAliases.html}{API Reference: ListAliases}
+#' \href{http://docs.aws.amazon.com/lambda/latest/dg/API_GetAlias.html}{API
+#' Reference: GetAlias}
+#' \href{http://docs.aws.amazon.com/lambda/latest/dg/API_CreateAlias.html}{API
+#' Reference: CreateAlias}
+#' \href{http://docs.aws.amazon.com/lambda/latest/dg/API_UpdateAlias.html}{API
+#' Reference: UpdateAlias}
+#' \href{http://docs.aws.amazon.com/lambda/latest/dg/API_DeleteAlias.html}{API
+#' Reference: DeleteAlias}
+#' \href{http://docs.aws.amazon.com/lambda/latest/dg/API_ListAliases.html}{API
+#' Reference: ListAliases}
 #' @seealso \code{\link{create_function}}, \code{\link{list_functions}}
 #' @export
-create_function_alias <- function(name, alias, description, version, ...) {
-    name <- get_function_name(name)
-    act <- paste0("/2015-03-31/functions/", name, "/aliases")
-    b <- list(Description = description, FunctionVersion = version, Name = alias)
-    r <- lambdaHTTP(verb = "POST", action = act, body = b, ...)
-    return(r)
+create_function_alias <- function(name, alias, version, description, ...) {
+  name <- get_function_name(name)
+  act <- paste0("/2015-03-31/functions/", name, "/aliases")
+  b <- list(FunctionVersion = version, Name = alias)
+  # Description is optional.
+  if (!missing(description)) {
+    b[["Description"]] <- description
+  }
+  r <- lambdaHTTP(verb = "POST", action = act, body = b, ...)
+  return(r)
 }
 
 #' @rdname alias
 #' @export
-update_function_alias <- function(name, alias, description, version, ...) {
-    name <- get_function_name(name)
-    act <- paste0("/2015-03-31/functions/", name, "/aliases/", alias)
-    b <- list(Description = description, FunctionVersion = version)
-    r <- lambdaHTTP(verb = "PUT", action = act, body = b, ...)
-    return(r)
+update_function_alias <- function(name, alias, version, description, ...) {
+  name <- get_function_name(name)
+  act <- paste0("/2015-03-31/functions/", name, "/aliases/", alias)
+  b <- list()
+  if (!missing(version)) {
+    b[["FunctionVersion"]] <- version
+  }
+  if (!missing(description)) {
+    b[["Description"]] <- description
+  }
+  r <- lambdaHTTP(verb = "PUT", action = act, body = b, ...)
+  return(r)
 }
 
 #' @rdname alias
 #' @export
 delete_function_alias <- function(name, alias, ...) {
-    name <- get_function_name(name)
-    act <- paste0("/2015-03-31/functions/", name, "/aliases/", alias)
-    r <- lambdaHTTP(verb = "DELETE", action = act, ...)
-    return(r)
+  name <- get_function_name(name)
+  act <- paste0("/2015-03-31/functions/", name, "/aliases/", alias)
+  r <- lambdaHTTP(verb = "DELETE", action = act, ...)
+  return(r)
 }
 
 #' @rdname alias
 #' @export
 get_function_alias <- function(name, alias, ...) {
-    name <- get_function_name(name)
-    act <- paste0("/2015-03-31/functions/", name, "/aliases/", alias)
-    r <- lambdaHTTP(verb = "GET", action = act, ...)
-    return(r)
+  name <- get_function_name(name)
+  act <- paste0("/2015-03-31/functions/", name, "/aliases/", alias)
+  r <- lambdaHTTP(verb = "GET", action = act, ...)
+  return(r)
 }
 
 #' @rdname alias
 #' @export
 list_function_aliases <- function(name, version, marker, n, ...) {
-    name <- get_function_name(name)
-    act <- paste0("/2015-03-31/functions/", name, "/aliases")
-    query <- list(FunctionVersion = version, Marker = marker, MaxItems = n)
-    r <- lambdaHTTP(verb = "GET", action = act, query = query, ...)
-    return(r)
+  name <- get_function_name(name)
+  act <- paste0("/2015-03-31/functions/", name, "/aliases")
+  query <- list()
+  if (!missing(version)) {
+    if (version == "$LATEST") {
+      warning(
+        "The AWS API erroneously returns an empty list with version = $LATEST.",
+        "\n  You may want to try again without specifying a version."
+      )
+    }
+    query[["FunctionVersion"]] <- version
+  }
+  if (!missing(marker)) {
+    query[["Marker"]] <- marker
+  }
+  if (!missing(n)) {
+    query[["MaxItems"]] <- n
+  }
+  r <- lambdaHTTP(verb = "GET", action = act, query = query, ...)
+  return(r)
 }
diff --git a/man/alias.Rd b/man/alias.Rd
index 6ed9e70..00b6d4a 100644
--- a/man/alias.Rd
+++ b/man/alias.Rd
@@ -8,9 +8,9 @@
 \alias{list_function_aliases}
 \title{Alias Management}
 \usage{
-create_function_alias(name, alias, description, version, ...)
+create_function_alias(name, alias, version, description, ...)
 
-update_function_alias(name, alias, description, version, ...)
+update_function_alias(name, alias, version, description, ...)
 
 delete_function_alias(name, alias, ...)
 
@@ -23,10 +23,11 @@ list_function_aliases(name, version, marker, n, ...)
 
 \item{alias}{A character string specifying a function alias}
 
-\item{description}{Optionally, a max 256-character description of the function for your own use.}
-
 \item{version}{A character string specifying a function version}
 
+\item{description}{Optionally, a max 256-character description of the
+function for your own use.}
+
 \item{\dots}{Additional arguments passed to \code{\link{lambdaHTTP}}.}
 
 \item{marker}{A pagination marker from a previous request.}
@@ -40,14 +41,23 @@ An object of class \dQuote{aws_lambda_function}.
 List, create, update, and delete function aliases
 }
 \details{
-\code{list_functions} lists all functions. \code{get_function} retrieves a specific function and \code{get_function_versions} retrieves all versions of that function. \code{get_function_configuration} returns the configuration details used when creating or updating the function. \code{delete_function} deletes a function, if you have permission to do so.
+\code{list_functions} lists all functions. \code{get_function}
+  retrieves a specific function and \code{get_function_versions} retrieves
+  all versions of that function. \code{get_function_configuration} returns
+  the configuration details used when creating or updating the function.
+  \code{delete_function} deletes a function, if you have permission to do so.
 }
 \references{
-\href{http://docs.aws.amazon.com/lambda/latest/dg/API_GetAlias.html}{API Reference: GetAlias}
- \href{http://docs.aws.amazon.com/lambda/latest/dg/API_CreateAlias.html}{API Reference: CreateAlias}
- \href{http://docs.aws.amazon.com/lambda/latest/dg/API_UpdateAlias.html}{API Reference: UpdateAlias}
- \href{http://docs.aws.amazon.com/lambda/latest/dg/API_DeleteAlias.html}{API Reference: DeleteAlias}
- \href{http://docs.aws.amazon.com/lambda/latest/dg/API_ListAliases.html}{API Reference: ListAliases}
+\href{http://docs.aws.amazon.com/lambda/latest/dg/API_GetAlias.html}{API
+Reference: GetAlias}
+\href{http://docs.aws.amazon.com/lambda/latest/dg/API_CreateAlias.html}{API
+Reference: CreateAlias}
+\href{http://docs.aws.amazon.com/lambda/latest/dg/API_UpdateAlias.html}{API
+Reference: UpdateAlias}
+\href{http://docs.aws.amazon.com/lambda/latest/dg/API_DeleteAlias.html}{API
+Reference: DeleteAlias}
+\href{http://docs.aws.amazon.com/lambda/latest/dg/API_ListAliases.html}{API
+Reference: ListAliases}
 }
 \seealso{
 \code{\link{create_function}}, \code{\link{list_functions}}