diff --git a/examples/aiohttp/app.py b/examples/aiohttp/app.py
index da6397f..260636d 100755
--- a/examples/aiohttp/app.py
+++ b/examples/aiohttp/app.py
@@ -13,7 +13,7 @@ async def background_task():
     """Example of how to send server generated events to clients."""
     count = 0
     while True:
-        await asyncio.sleep(10)
+        await sio.sleep(10)
         count += 1
         await sio.emit('my response', {'data': 'Server generated event'},
                        namespace='/test')
@@ -84,5 +84,5 @@ app.router.add_get('/', index)
 
 
 if __name__ == '__main__':
-    asyncio.ensure_future(background_task())
+    sio.start_background_task(background_task)
     web.run_app(app)
diff --git a/socketio/asyncio_server.py b/socketio/asyncio_server.py
index c3dc312..857a97a 100644
--- a/socketio/asyncio_server.py
+++ b/socketio/asyncio_server.py
@@ -106,7 +106,7 @@ class AsyncServer(server.Server):
                              to always leave this parameter with its default
                              value of ``False``.
 
-        Note: this method is asynchronous.
+        Note: this method is a coroutine.
         """
         namespace = namespace or '/'
         self.logger.info('emitting event "%s" to %s [%s]', event,
@@ -148,7 +148,7 @@ class AsyncServer(server.Server):
                              to always leave this parameter with its default
                              value of ``False``.
 
-        Note: this method is asynchronous.
+        Note: this method is a coroutine.
         """
         await self.emit('message', data, room, skip_sid, namespace, callback,
                         **kwargs)
@@ -160,7 +160,7 @@ class AsyncServer(server.Server):
         :param namespace: The Socket.IO namespace to disconnect. If this
                           argument is omitted the default namespace is used.
 
-        Note: this method is asynchronous.
+        Note: this method is a coroutine.
         """
         namespace = namespace or '/'
         if self.manager.is_connected(sid, namespace=namespace):
@@ -185,18 +185,38 @@ class AsyncServer(server.Server):
         This function returns the HTTP response body to deliver to the client
         as a byte sequence.
 
-        Note: this method is asynchronous.
+        Note: this method is a coroutine.
         """
-        if not self.manager_initialized:
-            self.manager_initialized = True
-            self.manager.initialize()
         return await self.eio.handle_request(environ)
 
     def start_background_task(self, target, *args, **kwargs):
-        raise RuntimeError('Not implemented, use asyncio.')
+        """Start a background task using the appropriate async model.
+
+        This is a utility function that applications can use to start a
+        background task using the method that is compatible with the
+        selected async mode.
+
+        :param target: the target function to execute. Must be a coroutine.
+        :param args: arguments to pass to the function.
+        :param kwargs: keyword arguments to pass to the function.
+
+        The return value is a ``asyncio.Task`` object.
+
+        Note: this method is a coroutine.
+        """
+        return self.eio.start_background_task(target, *args, **kwargs)
+
+    async def sleep(self, seconds=0):
+        """Sleep for the requested amount of time using the appropriate async
+        model.
 
-    def sleep(self, seconds=0):
-        raise RuntimeError('Not implemented, use asyncio.')
+        This is a utility function that applications can use to put a task to
+        sleep without having to worry about using the correct call for the
+        selected async mode.
+
+        Note: this method is a coroutine.
+        """
+        return await self.eio.sleep(seconds)
 
     async def _emit_internal(self, sid, event, data, namespace=None, id=None):
         """Send a message to a client."""
@@ -301,6 +321,9 @@ class AsyncServer(server.Server):
 
     async def _handle_eio_connect(self, sid, environ):
         """Handle the Engine.IO connection event."""
+        if not self.manager_initialized:
+            self.manager_initialized = True
+            self.manager.initialize()
         self.environ[sid] = environ
         return await self._handle_connect(sid, '/')
 
diff --git a/socketio/server.py b/socketio/server.py
index 7975ec5..cd04a42 100644
--- a/socketio/server.py
+++ b/socketio/server.py
@@ -345,9 +345,6 @@ class Server(object):
         This function returns the HTTP response body to deliver to the client
         as a byte sequence.
         """
-        if not self.manager_initialized:
-            self.manager_initialized = True
-            self.manager.initialize()
         return self.eio.handle_request(environ, start_response)
 
     def start_background_task(self, target, *args, **kwargs):
@@ -485,6 +482,9 @@ class Server(object):
 
     def _handle_eio_connect(self, sid, environ):
         """Handle the Engine.IO connection event."""
+        if not self.manager_initialized:
+            self.manager_initialized = True
+            self.manager.initialize()
         self.environ[sid] = environ
         return self._handle_connect(sid, '/')
 
diff --git a/tests/test_server.py b/tests/test_server.py
index 36ad0f2..62262ee 100644
--- a/tests/test_server.py
+++ b/tests/test_server.py
@@ -30,7 +30,6 @@ class TestServer(unittest.TestCase):
         self.assertEqual(s.eio.on.call_count, 3)
         self.assertEqual(s.binary, True)
         self.assertEqual(s.async_handlers, True)
-        self.assertEqual(mgr.initialize.call_count, 1)
 
     def test_on_event(self, eio):
         s = server.Server()
@@ -180,6 +179,7 @@ class TestServer(unittest.TestCase):
         handler.assert_called_once_with('123', 'environ')
         s.manager.connect.assert_called_once_with('123', '/')
         s.eio.send.assert_called_once_with('123', '0', binary=False)
+        self.assertEqual(mgr.initialize.call_count, 1)
 
     def test_handle_connect_namespace(self, eio):
         mgr = mock.MagicMock()