diff --git a/islandora.api.php b/islandora.api.php
index e553a894..db1b6b0b 100644
--- a/islandora.api.php
+++ b/islandora.api.php
@@ -562,8 +562,14 @@ function hook_cmodel_pid_islandora_ingest_steps_alter(array &$steps, array &$for
  *   the given object, or NULL to indicate that we are making no assertion
  *   about the outcome. Can also be an array containing multiple
  *   TRUE/FALSE/NULLs, due to how hooks work.
+ *
+ *   If denying an action (such as ISLANDORA_VIEW_OBJECTS) on an object,
+ *   it will not be automatically denied for the individual datastreams.
+ *   Operations on datastreams must be explicitly denied in
+ *   hook_islandora_datastream_access().
+ *
  */
-function hook_islandora_object_access($op, $object, $user) {
+function hook_islandora_object_access($op, AbstractObject $object, $user) {
   switch ($op) {
     case 'create stuff':
       return TRUE;
@@ -591,8 +597,8 @@ function hook_cmodel_pid_islandora_object_access($op, $object, $user) {
  * @param string $op
  *   A string define an operation to check. Should be defined via
  *   hook_permission().
- * @param AbstractDatastream $object
- *   An object to check the operation on.
+ * @param AbstractDatastream $datastream
+ *   A datastream to check the operation on.
  * @param object $user
  *   A loaded user object, as the global $user variable might contain.
  *
@@ -602,7 +608,7 @@ function hook_cmodel_pid_islandora_object_access($op, $object, $user) {
  *   about the outcome. Can also be an array containing multiple
  *   TRUE/FALSE/NULLs, due to how hooks work.
  */
-function hook_islandora_datastream_access($op, $object, $user) {
+function hook_islandora_datastream_access($op, AbstractDatastream $datastream, $user) {
   switch ($op) {
     case 'create stuff':
       return TRUE;
@@ -620,7 +626,7 @@ function hook_islandora_datastream_access($op, $object, $user) {
  *
  * @see hook_islandora_datastream_access()
  */
-function hook_cmodel_pid_islandora_datastream_access($op, $object, $user) {
+function hook_cmodel_pid_islandora_datastream_access($op, $datastream, $user) {
 
 }
 
diff --git a/islandora.module b/islandora.module
index 0efc7cc4..ac892e6f 100644
--- a/islandora.module
+++ b/islandora.module
@@ -1967,11 +1967,11 @@ function islandora_islandora_metadata_display_info() {
  * Implements hook_islandora_datastream_access().
  */
 function islandora_islandora_datastream_access($op, AbstractDatastream $datastream, $user) {
-  module_load_include('inc', 'islandora', 'includes/utilities');
-  $result = islandora_namespace_accessible($datastream->parent->id) && user_access($op, $user);
+  $result = islandora_islandora_object_access($op, $datastream->parent, $user);
 
   if ($result && $op == ISLANDORA_REGENERATE_DERIVATIVES) {
     module_load_include('inc', 'islandora', 'includes/derivatives');
+    module_load_include('inc', 'islandora', 'includes/utilities');
     $applicable_hook = FALSE;
     $object = $datastream->parent;
     $hooks = islandora_invoke_hook_list(ISLANDORA_DERIVATIVE_CREATION_HOOK, $object->models, array($object));