diff --git a/compute_hyperv/nova/driver.py b/compute_hyperv/nova/driver.py
index f44b8172..a1b1177d 100644
--- a/compute_hyperv/nova/driver.py
+++ b/compute_hyperv/nova/driver.py
@@ -103,6 +103,7 @@ class HyperVDriver(driver.ComputeDriver):
         "supports_device_tagging": True,
         "supports_tagged_attach_interface": True,
         "supports_tagged_attach_volume": True,
+        "supports_extend_volume": True,
     }
 
     def __init__(self, virtapi):
@@ -198,6 +199,9 @@ class HyperVDriver(driver.ComputeDriver):
                                       instance,
                                       update_device_metadata=True)
 
+    def extend_volume(self, connection_info, instance):
+        self._volumeops.extend_volume(connection_info)
+
     def get_volume_connector(self, instance):
         return self._volumeops.get_volume_connector()
 
diff --git a/compute_hyperv/nova/volumeops.py b/compute_hyperv/nova/volumeops.py
index 32763de6..af22351d 100644
--- a/compute_hyperv/nova/volumeops.py
+++ b/compute_hyperv/nova/volumeops.py
@@ -375,6 +375,10 @@ class VolumeOps(object):
         volume_driver = self._get_volume_driver(connection_info)
         return volume_driver.get_disk_attachment_info(connection_info)
 
+    def extend_volume(self, connection_info):
+        volume_driver = self._get_volume_driver(connection_info)
+        return volume_driver.extend_volume(connection_info)
+
 
 class BaseVolumeDriver(object):
     _is_block_dev = True
@@ -543,6 +547,11 @@ class BaseVolumeDriver(object):
             is_physical=self._is_block_dev,
             serial=serial)
 
+    def extend_volume(self, connection_info):
+        # We're not actually extending the volume, we're just
+        # refreshing cached information about an already extended volume.
+        self._connector.extend_volume(connection_info['data'])
+
 
 class ISCSIVolumeDriver(BaseVolumeDriver):
     _is_block_dev = True
diff --git a/compute_hyperv/tests/unit/test_driver.py b/compute_hyperv/tests/unit/test_driver.py
index dc40a676..00eee158 100644
--- a/compute_hyperv/tests/unit/test_driver.py
+++ b/compute_hyperv/tests/unit/test_driver.py
@@ -226,6 +226,14 @@ class HyperVDriverTestCase(test_base.HyperVBaseTestCase):
             mock_instance,
             update_device_metadata=True)
 
+    def test_extend_volume(self):
+        mock_instance = fake_instance.fake_instance_obj(self.context)
+        self.driver.extend_volume(
+            mock.sentinel.connection_info, mock_instance)
+
+        self.driver._volumeops.extend_volume.assert_called_once_with(
+            mock.sentinel.connection_info)
+
     def test_get_volume_connector(self):
         self.driver.get_volume_connector(mock.sentinel.instance)
         self.driver._volumeops.get_volume_connector.assert_called_once_with()
diff --git a/compute_hyperv/tests/unit/test_volumeops.py b/compute_hyperv/tests/unit/test_volumeops.py
index c7d28974..e3084337 100644
--- a/compute_hyperv/tests/unit/test_volumeops.py
+++ b/compute_hyperv/tests/unit/test_volumeops.py
@@ -516,6 +516,15 @@ class VolumeOpsTestCase(test_base.HyperVBaseTestCase):
             mock_vol_driver.get_disk_attachment_info.return_value,
             ret_val)
 
+    @mock.patch.object(volumeops.VolumeOps, '_get_volume_driver')
+    def test_extend_volume(self, mock_get_volume_driver):
+        fake_conn_info = get_fake_connection_info()
+        self._volumeops.extend_volume(fake_conn_info)
+
+        mock_vol_driver = mock_get_volume_driver.return_value
+        mock_vol_driver.extend_volume.assert_called_once_with(
+            fake_conn_info)
+
 
 @ddt.ddt
 class BaseVolumeDriverTestCase(test_base.HyperVBaseTestCase):
@@ -814,6 +823,14 @@ class BaseVolumeDriverTestCase(test_base.HyperVBaseTestCase):
             is_physical=is_block_dev,
             serial=exp_serial)
 
+    def test_extend_volume(self):
+        conn_info = get_fake_connection_info()
+
+        self._base_vol_driver.extend_volume(conn_info)
+
+        self._conn.extend_volume.assert_called_once_with(
+            conn_info['data'])
+
 
 class ISCSIVolumeDriverTestCase(test_base.HyperVBaseTestCase):
     """Unit tests for Hyper-V BaseVolumeDriver class."""