diff --git a/glance/api/v1/images.py b/glance/api/v1/images.py
index 0ffcb2b05c..8697e0238f 100644
--- a/glance/api/v1/images.py
+++ b/glance/api/v1/images.py
@@ -34,6 +34,7 @@ from webob.exc import (HTTPError,
 from glance.api import common
 from glance.api import policy
 import glance.api.v1
+from glance import context
 from glance.api.v1 import controller
 from glance.api.v1 import filters
 from glance.common import exception
@@ -251,9 +252,9 @@ class Controller(controller.BaseController):
         return Controller._validate_source(source, req)
 
     @staticmethod
-    def _get_from_store(where):
+    def _get_from_store(context, where):
         try:
-            image_data, image_size = get_from_backend(where)
+            image_data, image_size = get_from_backend(context, where)
         except exception.NotFound, e:
             raise HTTPNotFound(explanation="%s" % e)
         image_size = int(image_size) if image_size else None
@@ -275,7 +276,8 @@ class Controller(controller.BaseController):
         if image_meta.get('size') == 0:
             image_iterator = iter([])
         else:
-            image_iterator, size = self._get_from_store(image_meta['location'])
+            image_iterator, size = self._get_from_store(req.context,
+                                                        image_meta['location'])
             image_iterator = utils.cooperative_iter(image_iterator)
             image_meta['size'] = size or image_meta['size']
 
@@ -310,7 +312,8 @@ class Controller(controller.BaseController):
             self.get_store_or_400(req, store)
 
             # retrieve the image size from remote store (if not provided)
-            image_meta['size'] = self._get_size(image_meta, location)
+            image_meta['size'] = self._get_size(req.context, image_meta,
+                                                location)
         else:
             # Ensure that the size attribute is set to zero for directly
             # uploadable images (if not provided). The size will be set
@@ -357,7 +360,8 @@ class Controller(controller.BaseController):
 
         copy_from = self._copy_from(req)
         if copy_from:
-            image_data, image_size = self._get_from_store(copy_from)
+            image_data, image_size = self._get_from_store(req.context,
+                                                          copy_from)
             image_meta['size'] = image_size or image_meta['size']
         else:
             try:
@@ -555,9 +559,10 @@ class Controller(controller.BaseController):
         location = self._upload(req, image_meta)
         return self._activate(req, image_id, location)
 
-    def _get_size(self, image_meta, location):
+    def _get_size(self, context, image_meta, location):
         # retrieve the image size from remote store (if not provided)
-        return image_meta.get('size', 0) or get_size_from_backend(location)
+        return image_meta.get('size', 0) or get_size_from_backend(context,
+                                                                  location)
 
     def _handle_source(self, req, image_id, image_meta, image_data):
         if image_data or self._copy_from(req):
@@ -675,7 +680,8 @@ class Controller(controller.BaseController):
 
         try:
             if location:
-                image_meta['size'] = self._get_size(image_meta, location)
+                image_meta['size'] = self._get_size(req.context, image_meta,
+                                                    location)
 
             image_meta = registry.update_image_metadata(req.context,
                                                         id,
@@ -781,7 +787,7 @@ class Controller(controller.BaseController):
         :raises HTTPNotFound if store does not exist
         """
         try:
-            return get_store_from_scheme(scheme)
+            return get_store_from_scheme(request.context, scheme)
         except exception.UnknownScheme:
             msg = _("Store for scheme %s not found")
             LOG.error(msg % scheme)
@@ -797,7 +803,7 @@ class Controller(controller.BaseController):
         :param scheme: The backend store scheme
         """
         try:
-            get_store_from_scheme(scheme)
+            get_store_from_scheme(context.RequestContext(), scheme)
         except exception.UnknownScheme:
             msg = _("Store for scheme %s not found")
             LOG.error(msg % scheme)
diff --git a/glance/api/v2/image_data.py b/glance/api/v2/image_data.py
index 5e3f79847f..459c4d525a 100644
--- a/glance/api/v2/image_data.py
+++ b/glance/api/v2/image_data.py
@@ -40,7 +40,7 @@ class ImageDataController(object):
         self._get_image(req.context, image_id)
         try:
             location, size, checksum = self.store_api.add_to_backend(
-                    'file', image_id, data, size)
+                    req.context, 'file', image_id, data, size)
         except exception.Duplicate:
             raise webob.exc.HTTPConflict()
 
@@ -48,10 +48,12 @@ class ImageDataController(object):
         self.db_api.image_update(req.context, image_id, values)
 
     def download(self, req, image_id):
-        image = self._get_image(req.context, image_id)
+        ctx = req.context
+        image = self._get_image(ctx, image_id)
         location = image['location']
         if location:
-            image_data, image_size = self.store_api.get_from_backend(location)
+            image_data, image_size = self.store_api.get_from_backend(ctx,
+                                                                     location)
             return {'data': image_data, 'size': image_size}
         else:
             raise webob.exc.HTTPNotFound(_("No image data could be found"))
diff --git a/glance/image_cache/prefetcher.py b/glance/image_cache/prefetcher.py
index 7f15781eb3..dd9081e9c3 100644
--- a/glance/image_cache/prefetcher.py
+++ b/glance/image_cache/prefetcher.py
@@ -60,7 +60,7 @@ class Prefetcher(base.CacheApp):
             LOG.warn(_("No metadata found for image '%s'"), image_id)
             return False
 
-        image_data, image_size = get_from_backend(image_meta['location'])
+        image_data, image_size = get_from_backend(ctx, image_meta['location'])
         LOG.debug(_("Caching image '%s'"), image_id)
         self.cache.cache_image_iter(image_id, image_data)
         return True
diff --git a/glance/store/__init__.py b/glance/store/__init__.py
index 369f37e403..2c3a046869 100644
--- a/glance/store/__init__.py
+++ b/glance/store/__init__.py
@@ -46,9 +46,6 @@ store_opts = [
 CONF = cfg.CONF
 CONF.register_opts(store_opts)
 
-# Set of store objects, constructed in create_stores()
-STORES = {}
-
 
 class ImageAddResult(object):
 
@@ -161,6 +158,7 @@ def create_stores():
     from the given config. Duplicates are not re-registered.
     """
     store_count = 0
+    store_classes = set()
     for store_entry in CONF.known_stores:
         store_entry = store_entry.strip()
         if not store_entry:
@@ -173,10 +171,10 @@ def create_stores():
                                    'No schemes associated with it.'
                                    % store_cls)
         else:
-            if store_cls not in STORES:
+            if store_cls not in store_classes:
                 LOG.debug("Registering store %s with schemes %s",
                           store_cls, schemes)
-                STORES[store_cls] = store_instance
+                store_classes.add(store_cls)
                 scheme_map = {}
                 for scheme in schemes:
                     loc_cls = store_instance.get_store_location_class()
@@ -191,7 +189,7 @@ def create_stores():
     return store_count
 
 
-def get_store_from_scheme(scheme):
+def get_store_from_scheme(context, scheme):
     """
     Given a scheme, return the appropriate store object
     for handling that scheme.
@@ -199,10 +197,11 @@ def get_store_from_scheme(scheme):
     if scheme not in location.SCHEME_TO_CLS_MAP:
         raise exception.UnknownScheme(scheme=scheme)
     scheme_info = location.SCHEME_TO_CLS_MAP[scheme]
-    return STORES[scheme_info['store_class']]
+    store = scheme_info['store_class'](context)
+    return store
 
 
-def get_store_from_uri(uri):
+def get_store_from_uri(context, uri):
     """
     Given a URI, return the store object that would handle
     operations on the URI.
@@ -210,30 +209,31 @@ def get_store_from_uri(uri):
     :param uri: URI to analyze
     """
     scheme = uri[0:uri.find('/') - 1]
-    return get_store_from_scheme(scheme)
+    store = get_store_from_scheme(context, scheme)
+    return store
 
 
-def get_from_backend(uri, **kwargs):
+def get_from_backend(context, uri, **kwargs):
     """Yields chunks of data from backend specified by uri"""
 
-    store = get_store_from_uri(uri)
+    store = get_store_from_uri(context, uri)
     loc = location.get_location_from_uri(uri)
 
     return store.get(loc)
 
 
-def get_size_from_backend(uri):
+def get_size_from_backend(context, uri):
     """Retrieves image size from backend specified by uri"""
 
-    store = get_store_from_uri(uri)
+    store = get_store_from_uri(context, uri)
     loc = location.get_location_from_uri(uri)
 
     return store.get_size(loc)
 
 
-def delete_from_backend(uri, **kwargs):
+def delete_from_backend(context, uri, **kwargs):
     """Removes chunks of data from backend specified by uri"""
-    store = get_store_from_uri(uri)
+    store = get_store_from_uri(context, uri)
     loc = location.get_location_from_uri(uri)
 
     try:
@@ -262,7 +262,7 @@ def schedule_delete_from_backend(uri, context, image_id, **kwargs):
         registry.update_image_metadata(context, image_id,
                                        {'status': 'deleted'})
         try:
-            return delete_from_backend(uri, **kwargs)
+            return delete_from_backend(context, uri, **kwargs)
         except (UnsupportedBackend,
                 exception.StoreDeleteNotSupported,
                 exception.NotFound):
@@ -293,6 +293,6 @@ def schedule_delete_from_backend(uri, context, image_id, **kwargs):
                                    {'status': 'pending_delete'})
 
 
-def add_to_backend(scheme, image_id, data, size):
-    store = get_store_from_scheme(scheme)
+def add_to_backend(context, scheme, image_id, data, size):
+    store = get_store_from_scheme(context, scheme)
     return store.add(image_id, data, size)
diff --git a/glance/store/base.py b/glance/store/base.py
index 0d8c76bb4f..2594cdf53b 100644
--- a/glance/store/base.py
+++ b/glance/store/base.py
@@ -28,11 +28,12 @@ class Store(object):
 
     CHUNKSIZE = (16 * 1024 * 1024)  # 16M
 
-    def __init__(self):
+    def __init__(self, context=None):
         """
         Initialize the Store
         """
         self.store_location_class = None
+        self.context = context
         self.configure()
 
         try:
diff --git a/glance/store/scrubber.py b/glance/store/scrubber.py
index 1265f46493..d6ff5f9cec 100644
--- a/glance/store/scrubber.py
+++ b/glance/store/scrubber.py
@@ -20,11 +20,11 @@ import eventlet
 import os
 import time
 
+from glance import context
 from glance.common import utils
 from glance.openstack.common import cfg
 import glance.openstack.common.log as logging
 from glance import registry
-from glance.registry import client
 from glance import store
 import glance.store.filesystem
 import glance.store.http
@@ -74,6 +74,9 @@ class Scrubber(object):
         self.datadir = CONF.scrubber_datadir
         self.cleanup = CONF.cleanup_scrubber
         self.cleanup_time = CONF.cleanup_scrubber_time
+        # configs for registry API store auth
+        self.admin_user = CONF.admin_user
+        self.admin_tenant = CONF.admin_tenant_name
 
         host, port = CONF.registry_host, CONF.registry_port
 
@@ -82,7 +85,10 @@ class Scrubber(object):
                   'cleanup_time': self.cleanup_time,
                   'registry_host': host, 'registry_port': port})
 
-        self.registry = client.RegistryClient(host, port)
+        registry.configure_registry_client()
+        registry.configure_registry_admin_creds()
+        ctx = context.RequestContext()
+        self.registry = registry.get_registry_client(ctx)
 
         utils.safe_mkdirs(self.datadir)
 
@@ -124,7 +130,12 @@ class Scrubber(object):
         file_path = os.path.join(self.datadir, str(id))
         try:
             LOG.debug(_("Deleting %(uri)s") % {'uri': uri})
-            store.delete_from_backend(uri)
+            # Here we create a request context with credentials to support
+            # delayed delete when using multi-tenant backend storage
+            ctx = context.RequestContext(auth_tok=self.registry.auth_tok,
+                                         user=self.admin_user,
+                                         tenant=self.admin_tenant)
+            store.delete_from_backend(ctx, uri)
         except store.UnsupportedBackend:
             msg = _("Failed to delete image from store (%(uri)s).")
             LOG.error(msg % {'uri': uri})
diff --git a/glance/tests/unit/base.py b/glance/tests/unit/base.py
index 5db08fff19..6cafab353c 100644
--- a/glance/tests/unit/base.py
+++ b/glance/tests/unit/base.py
@@ -36,14 +36,12 @@ class StoreClearingUnitTest(test_utils.BaseTestCase):
     def setUp(self):
         super(StoreClearingUnitTest, self).setUp()
         # Ensure stores + locations cleared
-        store.STORES = {}
         location.SCHEME_TO_CLS_MAP = {}
         store.create_stores()
 
     def tearDown(self):
         super(StoreClearingUnitTest, self).tearDown()
         # Ensure stores + locations cleared
-        store.STORES = {}
         location.SCHEME_TO_CLS_MAP = {}
 
 
diff --git a/glance/tests/unit/test_http_store.py b/glance/tests/unit/test_http_store.py
index ea93cc8130..84a71564c8 100644
--- a/glance/tests/unit/test_http_store.py
+++ b/glance/tests/unit/test_http_store.py
@@ -125,9 +125,10 @@ class TestHttpStore(base.StoreClearingUnitTest):
     def test_http_delete_raise_error(self):
         uri = "https://netloc/path/to/file.tar.gz"
         loc = get_location_from_uri(uri)
+        ctx = context.RequestContext()
         self.assertRaises(NotImplementedError, self.store.delete, loc)
         self.assertRaises(exception.StoreDeleteNotSupported,
-                          delete_from_backend, uri)
+                          delete_from_backend, ctx, uri)
 
     def test_http_schedule_delete_swallows_error(self):
         uri = "https://netloc/path/to/file.tar.gz"
diff --git a/glance/tests/unit/test_store_location.py b/glance/tests/unit/test_store_location.py
index 4e78930420..2fd61e8154 100644
--- a/glance/tests/unit/test_store_location.py
+++ b/glance/tests/unit/test_store_location.py
@@ -15,6 +15,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from glance import context
 from glance.common import exception
 import glance.store
 import glance.store.filesystem
@@ -275,8 +276,9 @@ class TestStoreLocation(base.StoreClearingUnitTest):
             'http': glance.store.http.Store,
             'https': glance.store.http.Store}
 
+        ctx = context.RequestContext()
         for scheme, store in good_results.items():
-            store_obj = glance.store.get_store_from_scheme(scheme)
+            store_obj = glance.store.get_store_from_scheme(ctx, scheme)
             self.assertEqual(store_obj.__class__, store)
 
         bad_results = ['fil', 'swift+h', 'unknown']
@@ -284,4 +286,5 @@ class TestStoreLocation(base.StoreClearingUnitTest):
         for store in bad_results:
             self.assertRaises(exception.UnknownScheme,
                               glance.store.get_store_from_scheme,
+                              ctx,
                               store)
diff --git a/glance/tests/unit/utils.py b/glance/tests/unit/utils.py
index 502a4b6f80..e40e34a7f7 100644
--- a/glance/tests/unit/utils.py
+++ b/glance/tests/unit/utils.py
@@ -91,7 +91,7 @@ class FakeStoreAPI(object):
     def create_stores(self):
         pass
 
-    def get_from_backend(self, location):
+    def get_from_backend(self, context, location):
         try:
             #NOTE(bcwaldon): This fake API is store-agnostic, so we only
             # care about location being some unique string
@@ -99,10 +99,10 @@ class FakeStoreAPI(object):
         except KeyError:
             raise exception.NotFound()
 
-    def get_size_from_backend(self, location):
-        return self.get_from_backend(location)[1]
+    def get_size_from_backend(self, context, location):
+        return self.get_from_backend(context, location)[1]
 
-    def add_to_backend(self, scheme, image_id, data, size):
+    def add_to_backend(self, context, scheme, image_id, data, size):
         if image_id in self.data:
             raise exception.Duplicate()
         self.data[image_id] = (data, size or len(data))