diff --git a/rally/plugins/openstack/context/existing_network.py b/rally/plugins/openstack/context/existing_network.py
new file mode 100644
index 0000000000..f6e59ce41d
--- /dev/null
+++ b/rally/plugins/openstack/context/existing_network.py
@@ -0,0 +1,53 @@
+# All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+
+from rally.common.i18n import _
+from rally.common import log as logging
+from rally.common import utils
+from rally import consts
+from rally import osclients
+from rally.plugins.openstack.wrappers import network as network_wrapper
+from rally.task import context
+
+
+LOG = logging.getLogger(__name__)
+
+
+@context.configure(name="existing_network", order=349)
+class ExistingNetwork(context.Context):
+    """This context supports using existing networks in Rally.
+
+    This context should be used on a deployment with existing users.
+    """
+
+    CONFIG_SCHEMA = {
+        "type": "object",
+        "$schema": consts.JSON_SCHEMA,
+        "additionalProperties": False
+    }
+
+    @utils.log_task_wrapper(LOG.info, _("Enter context: `existing_network`"))
+    def setup(self):
+        for user, tenant_id in utils.iterate_per_tenants(
+                self.context.get("users", [])):
+            net_wrapper = network_wrapper.wrap(
+                osclients.Clients(user["endpoint"]),
+                self.config)
+            self.context["tenants"][tenant_id]["networks"] = (
+                net_wrapper.list_networks())
+
+    @utils.log_task_wrapper(LOG.info, _("Exit context: `existing_network`"))
+    def cleanup(self):
+        """Networks were not created by Rally, so nothing to do."""
diff --git a/rally/plugins/openstack/wrappers/network.py b/rally/plugins/openstack/wrappers/network.py
index 4a49958557..f5cbd1c520 100644
--- a/rally/plugins/openstack/wrappers/network.py
+++ b/rally/plugins/openstack/wrappers/network.py
@@ -112,6 +112,21 @@ class NovaNetworkWrapper(NetworkWrapper):
             cidr = generate_cidr(start_cidr=self.start_cidr)
         return cidr
 
+    def _marshal_network_object(self, net_obj):
+        """Convert a Network object to a dict.
+
+        This helps keep return values from the NovaNetworkWrapper
+        compatible with those from NeutronWrapper.
+
+        :param net_obj: The Network object to convert to a dict
+        """
+        return {"id": net_obj.id,
+                "cidr": net_obj.cidr,
+                "name": net_obj.label,
+                "status": "ACTIVE",
+                "external": False,
+                "tenant_id": net_obj.project_id}
+
     def create_network(self, tenant_id, **kwargs):
         """Create network.
 
@@ -123,18 +138,14 @@ class NovaNetworkWrapper(NetworkWrapper):
         label = utils.generate_random_name("rally_net_")
         network = self.client.networks.create(
             tenant_id=tenant_id, cidr=cidr, label=label)
-        return {"id": network.id,
-                "cidr": network.cidr,
-                "name": network.label,
-                "status": "ACTIVE",
-                "external": False,
-                "tenant_id": tenant_id}
+        return self._marshal_network_object(network)
 
     def delete_network(self, network):
         return self.client.networks.delete(network["id"])
 
     def list_networks(self):
-        return self.client.networks.list()
+        return [self._marshal_network_object(n)
+                for n in self.client.networks.list()]
 
     def create_floating_ip(self, ext_network=None, **kwargs):
         """Allocate a floating ip from the given nova-network pool
diff --git a/tests/unit/plugins/openstack/context/test_existing_network.py b/tests/unit/plugins/openstack/context/test_existing_network.py
new file mode 100644
index 0000000000..4ad1fbebde
--- /dev/null
+++ b/tests/unit/plugins/openstack/context/test_existing_network.py
@@ -0,0 +1,81 @@
+# All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import mock
+
+from rally.plugins.openstack.context import existing_network
+from tests.unit import test
+
+CTX = "rally.plugins.openstack.context"
+
+
+class ExistingNetworkTestCase(test.TestCase):
+
+    def setUp(self):
+        super(ExistingNetworkTestCase, self).setUp()
+
+        self.config = mock.MagicMock()
+        self.context = {
+            "task": mock.MagicMock(),
+            "users": [
+                {"id": 1,
+                 "tenant_id": "tenant1",
+                 "endpoint": mock.Mock()},
+                {"id": 2,
+                 "tenant_id": "tenant2",
+                 "endpoint": mock.Mock()},
+            ],
+            "tenants": {
+                "tenant1": {},
+                "tenant2": {},
+            },
+            "config": {
+                "existing_network": self.config
+            },
+        }
+
+    @mock.patch("rally.osclients.Clients")
+    @mock.patch("rally.plugins.openstack.wrappers.network.wrap")
+    def test_setup(self, mock_network_wrap, mock_clients):
+        networks = [mock.Mock(), mock.Mock(), mock.Mock()]
+        net_wrappers = {
+            "tenant1": mock.Mock(
+                **{"list_networks.return_value": networks[0:2]}),
+            "tenant2": mock.Mock(
+                **{"list_networks.return_value": networks[2:]})
+        }
+        mock_network_wrap.side_effect = [net_wrappers["tenant1"],
+                                         net_wrappers["tenant2"]]
+
+        existing_network.ExistingNetwork(self.context).setup()
+
+        mock_clients.assert_has_calls([
+            mock.call(u["endpoint"]) for u in self.context["users"]])
+        mock_network_wrap.assert_has_calls([
+            mock.call(mock_clients.return_value, self.config),
+            mock.call(mock_clients.return_value, self.config)])
+        for net_wrapper in net_wrappers.values():
+            net_wrapper.list_networks.assert_called_once_with()
+
+        self.assertDictEqual(
+            self.context["tenants"],
+            {
+                "tenant1": {"networks": networks[0:2]},
+                "tenant2": {"networks": networks[2:]},
+            }
+        )
+
+    def test_cleanup(self):
+        # NOTE(stpierre): Test that cleanup is not abstract
+        existing_network.ExistingNetwork({"task": mock.MagicMock()}).cleanup()
diff --git a/tests/unit/plugins/openstack/wrappers/test_network.py b/tests/unit/plugins/openstack/wrappers/test_network.py
index deae8b3ec7..1dee08226b 100644
--- a/tests/unit/plugins/openstack/wrappers/test_network.py
+++ b/tests/unit/plugins/openstack/wrappers/test_network.py
@@ -30,6 +30,8 @@ class NovaNetworkWrapperTestCase(test.TestCase):
 
     class Net(object):
         def __init__(self, **kwargs):
+            if "tenant_id" in kwargs:
+                kwargs["project_id"] = kwargs.pop("tenant_id")
             self.__dict__.update(kwargs)
 
     def get_wrapper(self, *skip_cidrs, **kwargs):
@@ -88,9 +90,18 @@ class NovaNetworkWrapperTestCase(test.TestCase):
 
     def test_list_networks(self):
         service = self.get_wrapper()
-        service.client.networks.list.return_value = "foo_list"
         service.client.networks.list.reset_mock()
-        self.assertEqual(service.list_networks(), "foo_list")
+        service.client.networks.list.return_value = [
+            self.Net(id="foo_id", project_id="foo_tenant", cidr="foo_cidr",
+                     label="foo_label"),
+            self.Net(id="bar_id", project_id="bar_tenant", cidr="bar_cidr",
+                     label="bar_label")]
+        expected = [
+            {"id": "foo_id", "cidr": "foo_cidr", "name": "foo_label",
+             "status": "ACTIVE", "external": False, "tenant_id": "foo_tenant"},
+            {"id": "bar_id", "cidr": "bar_cidr", "name": "bar_label",
+             "status": "ACTIVE", "external": False, "tenant_id": "bar_tenant"}]
+        self.assertEqual(expected, service.list_networks())
         service.client.networks.list.assert_called_once_with()
 
     def test__get_floating_ip(self):