diff --git a/keystoneauth1/loading/base.py b/keystoneauth1/loading/base.py
index 1a93f2e3..31277d2c 100644
--- a/keystoneauth1/loading/base.py
+++ b/keystoneauth1/loading/base.py
@@ -28,6 +28,11 @@ __all__ = ('get_available_plugin_names',
            'PLUGIN_NAMESPACE')
 
 
+def _auth_plugin_available(ext):
+    """Read the value of available for whether to load this plugin."""
+    return ext.obj.available
+
+
 def get_available_plugin_names():
     """Get the names of all the plugins that are available on the system.
 
@@ -37,7 +42,10 @@ def get_available_plugin_names():
     :returns: A list of names.
     :rtype: frozenset
     """
-    mgr = stevedore.ExtensionManager(namespace=PLUGIN_NAMESPACE)
+    mgr = stevedore.EnabledExtensionManager(namespace=PLUGIN_NAMESPACE,
+                                            check_func=_auth_plugin_available,
+                                            invoke_on_load=True,
+                                            propagate_map_exceptions=True)
     return frozenset(mgr.names())
 
 
@@ -48,9 +56,10 @@ def get_available_plugin_loaders():
               loader as the value.
     :rtype: dict
     """
-    mgr = stevedore.ExtensionManager(namespace=PLUGIN_NAMESPACE,
-                                     invoke_on_load=True,
-                                     propagate_map_exceptions=True)
+    mgr = stevedore.EnabledExtensionManager(namespace=PLUGIN_NAMESPACE,
+                                            check_func=_auth_plugin_available,
+                                            invoke_on_load=True,
+                                            propagate_map_exceptions=True)
 
     return dict(mgr.map(lambda ext: (ext.entry_point.name, ext.obj)))
 
@@ -109,6 +118,18 @@ class BaseLoader(object):
         """
         return []
 
+    @property
+    def available(self):
+        """Return if the plugin is available for loading.
+
+        If a plugin is missing dependencies or for some other reason should not
+        be available to the current system it should override this property and
+        return False to exclude itself from the plugin list.
+
+        :rtype: bool
+        """
+        return True
+
     def load_from_options(self, **kwargs):
         """Create a plugin from the arguments retrieved from get_options.