diff --git a/vmware_nsxlib/tests/unit/v3/test_security.py b/vmware_nsxlib/tests/unit/v3/test_security.py
index 46f5cb69..e17fc60d 100644
--- a/vmware_nsxlib/tests/unit/v3/test_security.py
+++ b/vmware_nsxlib/tests/unit/v3/test_security.py
@@ -188,10 +188,14 @@ class TestNsxLibNSGroup(nsxlib_testcase.NsxClientTestCase):
 
     def test_update(self):
         nsg_tags = [{"scope": "name", "tag": "new_name"}]
+        membership_criteria = []
         with mock.patch.object(self.nsxlib.client, 'update') as update:
             with mock.patch.object(self.nsxlib.client, 'get') as get:
                 get.return_value = {}
-                self.nsxlib.ns_group.update('nsgroupid', tags_update=nsg_tags)
+                self.nsxlib.ns_group.update(
+                    'nsgroupid', tags_update=nsg_tags,
+                    membership_criteria=membership_criteria)
                 resource = 'ns-groups/nsgroupid'
-                data = {'tags': nsg_tags}
+                data = {'tags': nsg_tags,
+                        'membership_criteria': membership_criteria}
                 update.assert_called_with(resource, data, headers=None)
diff --git a/vmware_nsxlib/v3/security.py b/vmware_nsxlib/v3/security.py
index 2e670ea8..aa5a5515 100644
--- a/vmware_nsxlib/v3/security.py
+++ b/vmware_nsxlib/v3/security.py
@@ -125,11 +125,11 @@ class NsxLibNsGroup(utils.NsxLibApiBase):
                 'tag': tag}
 
     def create(self, display_name, description, tags,
-               membership_criteria=None):
+               membership_criteria=None, members=None):
         body = {'display_name': display_name,
                 'description': description,
                 'tags': tags,
-                'members': []}
+                'members': [] if members is None else members}
         if membership_criteria:
             # Allow caller to pass a list of membership criterias.
             # The 'else' block is maintained for backwards compatibility
@@ -155,7 +155,10 @@ class NsxLibNsGroup(utils.NsxLibApiBase):
         if members is not None:
             nsgroup['members'] = members
         if membership_criteria is not None:
-            nsgroup['membership_criteria'] = [membership_criteria]
+            if isinstance(membership_criteria, list):
+                nsgroup['membership_criteria'] = membership_criteria
+            else:
+                nsgroup['membership_criteria'] = [membership_criteria]
         if tags_update is not None:
             nsgroup['tags_update'] = tags_update
         return self._update_resource(