diff --git a/letsencrypt/plugins/standalone.py b/letsencrypt/plugins/standalone.py
index 05a9f1655..551707263 100644
--- a/letsencrypt/plugins/standalone.py
+++ b/letsencrypt/plugins/standalone.py
@@ -39,8 +39,10 @@ class ServerManager(object):
     will serve the same URLs!
 
     """
+    _Instance = collections.namedtuple("_Instance", "server thread")
+
     def __init__(self, certs, simple_http_resources):
-        self._servers = {}
+        self._instances = {}
         self.certs = certs
         self.simple_http_resources = simple_http_resources
 
@@ -53,13 +55,12 @@ class ServerManager(object):
         :param int port: Port to run the server on.
         :param bool tls: TLS or non-TLS?
 
-        :returns: Server instance (`ACMEServerMixin`) and the
-            corresponding (already started) thread (`threading.Thread`).
-        :rtype: tuple
+        :returns: Server instance.
+        :rtype: ACMEServerMixin
 
         """
-        if port in self._servers:
-            return self._servers[port]
+        if port in self._instances:
+            return self._instances[port].server
 
         logger.debug("Starting new server at %s (tls=%s)", port, tls)
         handler = acme_standalone.ACMERequestHandler.partial_init(
@@ -84,8 +85,8 @@ class ServerManager(object):
         logger.debug("Starting server at %s:%d", host, real_port)
         thread.start()
 
-        self._servers[real_port] = (server, thread)
-        return self._servers[real_port]
+        self._instances[real_port] = self._Instance(server, thread)
+        return server
 
     def stop(self, port):
         """Stop ACME server running on the specified ``port``.
@@ -93,10 +94,10 @@ class ServerManager(object):
         :param int port:
 
         """
-        server, thread = self._servers[port]
-        server.shutdown2()
-        thread.join()
-        del self._servers[port]
+        instance = self._instances[port]
+        instance.server.shutdown2()
+        instance.thread.join()
+        del self._instances[port]
 
     def running(self):
         """Return all running instances.
@@ -104,11 +105,12 @@ class ServerManager(object):
         Once the server is stopped using `stop`, it will not be
         returned.
 
-        :returns: Mapping from port to ``(server, thread)``.
+        :returns: Mapping from ``port`` to ``server``.
         :rtype: tuple
 
         """
-        return self._servers.copy()
+        return dict((port, instance.server) for port, instance
+                    in six.iteritems(self._instances))
 
 
 SUPPORTED_CHALLENGES = set([challenges.DVSNI, challenges.SimpleHTTP])
@@ -233,7 +235,7 @@ class Authenticator(common.Plugin):
 
         for achall in achalls:
             if isinstance(achall, achallenges.SimpleHTTP):
-                server, _ = self.servers.run(self.config.simple_http_port, tls=tls)
+                server = self.servers.run(self.config.simple_http_port, tls=tls)
                 response, validation = achall.gen_response_and_validation(tls=tls)
                 self.simple_http_resources.add(
                     acme_standalone.SimpleHTTPRequestHandler.SimpleHTTPResource(
@@ -242,7 +244,7 @@ class Authenticator(common.Plugin):
                 cert = self.simple_http_cert
                 domain = achall.domain
             else:  # DVSNI
-                server, _ = self.servers.run(self.config.dvsni_port, tls=True)
+                server = self.servers.run(self.config.dvsni_port, tls=True)
                 response, cert, _ = achall.gen_cert_and_response(self.key)
                 domain = response.z_domain
             self.certs[domain] = (self.key, cert)
@@ -257,6 +259,6 @@ class Authenticator(common.Plugin):
             for achall in achalls:
                 if achall in server_achalls:
                     server_achalls.remove(achall)
-        for port, (server, _) in six.iteritems(self.servers.running()):
+        for port, server in six.iteritems(self.servers.running()):
             if not self.served[server]:
                 self.servers.stop(port)
diff --git a/letsencrypt/plugins/standalone_test.py b/letsencrypt/plugins/standalone_test.py
index 1cd310107..a45935d2b 100644
--- a/letsencrypt/plugins/standalone_test.py
+++ b/letsencrypt/plugins/standalone_test.py
@@ -33,9 +33,9 @@ class ServerManagerTest(unittest.TestCase):
             self.mgr.simple_http_resources is self.simple_http_resources)
 
     def _test_run_stop(self, tls):
-        server, _ = self.mgr.run(port=0, tls=tls)
-        port = server.socket.getsockname()[1]
-        self.assertEqual(self.mgr.running(), {port: (server, mock.ANY)})
+        server = self.mgr.run(port=0, tls=tls)
+        port = server.socket.getsockname()[1]  # pylint: disable=no-member
+        self.assertEqual(self.mgr.running(), {port: server})
         self.mgr.stop(port=port)
         self.assertEqual(self.mgr.running(), {})
 
@@ -46,12 +46,11 @@ class ServerManagerTest(unittest.TestCase):
         self._test_run_stop(tls=False)
 
     def test_run_idempotent(self):
-        server, thread = self.mgr.run(port=0, tls=False)
-        port = server.socket.getsockname()[1]
-        server2, thread2 = self.mgr.run(port=port, tls=False)
-        self.assertEqual(self.mgr.running(), {port: (server, thread)})
+        server = self.mgr.run(port=0, tls=False)
+        port = server.socket.getsockname()[1]  # pylint: disable=no-member
+        server2 = self.mgr.run(port=port, tls=False)
+        self.assertEqual(self.mgr.running(), {port: server})
         self.assertTrue(server is server2)
-        self.assertTrue(thread is thread2)
         self.mgr.stop(port)
         self.assertEqual(self.mgr.running(), {})
 
@@ -166,7 +165,7 @@ class AuthenticatorTest(unittest.TestCase):
         self.auth.servers = mock.MagicMock()
 
         def _run(port, tls):  # pylint: disable=unused-argument
-            return "server{0}".format(port), "thread{0}".format(port)
+            return "server{0}".format(port)
 
         self.auth.servers.run.side_effect = _run
         responses = self.auth.perform2([simple_http, dvsni])
@@ -191,8 +190,8 @@ class AuthenticatorTest(unittest.TestCase):
     def test_cleanup(self):
         self.auth.servers = mock.Mock()
         self.auth.servers.running.return_value = {
-            1: ("server1", "thread1"),
-            2: ("server2", "thread2"),
+            1: "server1",
+            2: "server2",
         }
         self.auth.served["server1"].add("chall1")
         self.auth.served["server2"].update(["chall2", "chall3"])
@@ -203,7 +202,7 @@ class AuthenticatorTest(unittest.TestCase):
         self.auth.servers.stop.assert_called_once_with(1)
 
         self.auth.servers.running.return_value = {
-            2: ("server2", "thread2"),
+            2: "server2",
         }
         self.auth.cleanup(["chall2"])
         self.assertEqual(self.auth.served, {