diff --git a/zaza/openstack/charm_tests/glance/setup.py b/zaza/openstack/charm_tests/glance/setup.py
index 6686d70..367c980 100644
--- a/zaza/openstack/charm_tests/glance/setup.py
+++ b/zaza/openstack/charm_tests/glance/setup.py
@@ -14,7 +14,11 @@
 
 """Code for configuring glance."""
 
+import json
 import logging
+
+import boto3
+import zaza.model as model
 import zaza.openstack.utilities.openstack as openstack_utils
 import zaza.utilities.deployment_env as deployment_env
 
@@ -161,3 +165,58 @@ def add_lts_image(glance_client=None, image_name=None, release=None,
               glance_client=glance_client,
               image_name=image_name,
               properties=properties)
+
+
+def configure_external_s3_backend():
+    """Set up Ceph-radosgw as an external S3 backend for Glance."""
+    logging.info("Creating a test S3 user and credentials for Glance")
+    username, displayname = "zaza-glance-test", "Zaza Glance Test User"
+    cmd = "radosgw-admin user create --uid='{}' --display-name='{}'".format(
+        username, displayname
+    )
+    results = model.run_on_leader("ceph-mon", cmd)
+    stdout = json.loads(results["stdout"])
+    keys = stdout["keys"][0]
+    access_key, secret_key = keys["access_key"], keys["secret_key"]
+
+    logging.info("Getting S3 endpoint URL of Radosgw from Keystone")
+    keystone_auth = openstack_utils.get_overcloud_auth()
+    keystone_client = openstack_utils.get_keystone_client(keystone_auth)
+    endpoint_url = keystone_client.session.get_endpoint(
+        service_type="s3",
+        interface="public",
+        region="RegionOne",
+    )
+
+    logging.info("Creating a test S3 bucket for Glance")
+    bucket_name = "zaza-glance-s3-test"
+    s3_client = boto3.client(
+        "s3",
+        endpoint_url=endpoint_url,
+        aws_access_key_id=access_key,
+        aws_secret_access_key=secret_key,
+    )
+    s3_client.create_bucket(Bucket=bucket_name)
+
+    logging.info("Updating Glance configs with S3 endpoint information")
+    model.set_application_config(
+        "glance",
+        {
+            "s3-store-host": endpoint_url,
+            "s3-store-access-key": access_key,
+            "s3-store-secret-key": secret_key,
+            "s3-store-bucket": bucket_name,
+        },
+    )
+    model.wait_for_agent_status()
+
+    logging.info("Waiting for units to reach target states")
+    model.wait_for_application_states(
+        states={
+            "glance": {
+                "workload-status": "active",
+                "workload-status-message": "Unit is ready",
+            }
+        }
+    )
+    model.block_until_all_units_idle()
diff --git a/zaza/openstack/charm_tests/glance/tests.py b/zaza/openstack/charm_tests/glance/tests.py
index d81e440..a6da291 100644
--- a/zaza/openstack/charm_tests/glance/tests.py
+++ b/zaza/openstack/charm_tests/glance/tests.py
@@ -18,8 +18,10 @@
 
 import logging
 
-import zaza.openstack.utilities.openstack as openstack_utils
+import boto3
+import zaza.model as model
 import zaza.openstack.charm_tests.test_utils as test_utils
+import zaza.openstack.utilities.openstack as openstack_utils
 
 
 class GlanceTest(test_utils.OpenStackBaseTest):
@@ -168,3 +170,55 @@ class GlanceCephRGWBackendTest(test_utils.OpenStackBaseTest):
             'image size {}'.format(image['size'], total_bytes))
         self.assertEqual(image['size'], total_bytes)
         openstack_utils.delete_image(self.glance_client, image['id'])
+
+
+class GlanceExternalS3Test(test_utils.OpenStackBaseTest):
+    """Encapsulate glance tests using an external S3 backend."""
+
+    @classmethod
+    def setUpClass(cls):
+        """Run class setup for running glance tests with S3 backend."""
+        super(GlanceExternalS3Test, cls).setUpClass()
+        cls.glance_client = openstack_utils.get_glance_session_client(
+            cls.keystone_session
+        )
+
+        configs = model.get_application_config("glance")
+        cls.s3_store_host = configs["s3-store-host"]["value"]
+        cls.s3_store_access_key = configs["s3-store-access-key"]["value"]
+        cls.s3_store_secret_key = configs["s3-store-secret-key"]["value"]
+        cls.s3_store_bucket = configs["s3-store-bucket"]["value"]
+
+    def test_100_create_delete_image(self):
+        """Create an image and do a simple validation of it.
+
+        Validate the size of the image in both Glance API and actual S3 bucket.
+        """
+        image_name = "zaza-s3-test-image"
+        openstack_utils.create_image(
+            glance=self.glance_client,
+            image_url=openstack_utils.find_cirros_image(arch="x86_64"),
+            image_name=image_name,
+            backend="s3",
+        )
+        images = openstack_utils.get_images_by_name(
+            self.glance_client, image_name
+        )
+        self.assertEqual(len(images), 1)
+        image = images[0]
+
+        s3_client = boto3.client(
+            "s3",
+            endpoint_url=self.s3_store_host,
+            aws_access_key_id=self.s3_store_access_key,
+            aws_secret_access_key=self.s3_store_secret_key,
+        )
+        response = s3_client.head_object(
+            Bucket=self.s3_store_bucket, Key=image["id"]
+        )
+        logging.info(
+            "Checking glance image size {} matches S3 object's ContentLength "
+            "{}".format(image["size"], response["ContentLength"])
+        )
+        self.assertEqual(image["size"], response["ContentLength"])
+        openstack_utils.delete_image(self.glance_client, image["id"])