diff --git a/doc/testing.rst b/doc/testing.rst
index 5e427dd..3ed0f36 100644
--- a/doc/testing.rst
+++ b/doc/testing.rst
@@ -57,3 +57,16 @@ If you wish to run tests against a particular Twisted reactor, use ``--reactor=R
 * poll
 * selects
 * libevent  (requires pyevent)
+
+Writing Tests
+-------------
+
+What follows are some notes on writing tests, in no particular order.
+
+The filename convention when writing a test for module `foo` is to name the test `foo_test.py`.  We don't yet have a convention for tests that are of finer granularity, but a sensible one might be `foo_class_test.py`.
+
+If you are writing a test that involves a client connecting to a spawned server, it is best to not use a hardcoded port because that makes it harder to parallelize tests.  Instead bind the server to 0, and then look up its port when connecting the client, like this::
+
+  server_sock = api.tcp_listener(('127.0.0.1', 0))
+  client_sock = api.connect_tcp(('localhost', server_sock.getsockname()[1]))
+
diff --git a/tests/greenio_test.py b/tests/greenio_test.py
index 9ce9acb..0d914ae 100644
--- a/tests/greenio_test.py
+++ b/tests/greenio_test.py
@@ -257,10 +257,10 @@ class SSLTest(LimitedTestCase):
             stuff = sock.read(8192)
             sock.write('response')
   
-        sock = api.ssl_listener(('', 4201), self.certificate_file, self.private_key_file)
+        sock = api.ssl_listener(('127.0.0.1', 0), self.certificate_file, self.private_key_file)
         server_coro = coros.execute(serve, sock)
         
-        client = util.wrap_ssl(api.connect_tcp(('localhost', 4201)))
+        client = util.wrap_ssl(api.connect_tcp(('127.0.0.1', sock.getsockname()[1])))
         client.write('line 1\r\nline 2\r\n\r\n')
         self.assertEquals(client.read(8192), 'response')
         server_coro.wait()
@@ -271,11 +271,11 @@ class SSLTest(LimitedTestCase):
             sock.write('content')
             sock.shutdown()
             sock.close()
-        listener = api.ssl_listener(('', 4209), 
+        listener = api.ssl_listener(('', 0), 
                                     self.certificate_file, 
                                     self.private_key_file)
         killer = api.spawn(serve, listener)
-        client = util.wrap_ssl(api.connect_tcp(('localhost', 4209)))
+        client = util.wrap_ssl(api.connect_tcp(('localhost', listener.getsockname()[1])))
         client = greenio.GreenSSLObject(client)
         self.assertEquals(client.read(1024), 'content')
         self.assertEquals(client.read(1024), '')
diff --git a/tests/test__refcount.py b/tests/test__refcount.py
index 1df1fb3..365e20b 100644
--- a/tests/test__refcount.py
+++ b/tests/test__refcount.py
@@ -31,17 +31,15 @@ from eventlet.green.time import sleep
 import weakref
 import gc
 
-address = ('0.0.0.0', 7878)
-
 SOCKET_TIMEOUT = 0.1
 
 def init_server():
     s = socket.socket()
     s.settimeout(SOCKET_TIMEOUT)
     s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
-    s.bind(address)
+    s.bind(('localhost', 0))
     s.listen(5)
-    return s
+    return s, s.getsockname()[1]
 
 def handle_request(s, raise_on_timeout):
     try:
@@ -60,10 +58,10 @@ def handle_request(s, raise_on_timeout):
     #print 'handle_request - conn refcount: %s' % sys.getrefcount(conn)
     #conn.close()
 
-def make_request():
+def make_request(port):
     #print 'make_request'
     s = socket.socket()
-    s.connect(address)
+    s.connect(('localhost', port))
     #print 'make_request - connected'
     res = s.send('hello')
     #print 'make_request - sent %s' % res
@@ -73,10 +71,10 @@ def make_request():
     #s.close()
 
 def run_interaction(run_client):
-    s = init_server()
+    s, port = init_server()
     start_new_thread(handle_request, (s, run_client))
     if run_client:
-        start_new_thread(make_request, ())
+        start_new_thread(make_request, (port,))
     sleep(0.1+SOCKET_TIMEOUT)
     #print sys.getrefcount(s.fd)
     #s.close()