diff --git a/docs/client.rst b/docs/client.rst
index d929d75..e788d25 100644
--- a/docs/client.rst
+++ b/docs/client.rst
@@ -45,7 +45,7 @@ functions must be defined using the ``on`` decorator::
 
     @sio.on('connect')
     def on_connect():
-        print('I'm connected!')
+        print('I\'m connected!')
 
     @sio.on('message')
     def on_message(data):
@@ -57,7 +57,7 @@ functions must be defined using the ``on`` decorator::
 
     @sio.on('disconnect')
     def on_disconnect():
-        print('I'm disconnected!')
+        print('I\'m disconnected!')
 
 For the ``asyncio`` server, event handlers can be regular functions as above,
 or can also be coroutines::
@@ -162,7 +162,7 @@ added to the ``on`` decorator::
 
     @sio.on('connect', namespace='/chat')
     def on_connect():
-        print('I'm connected to the /chat namespace!')
+        print('I\'m connected to the /chat namespace!')
 
 Likewise, the client can emit an event to the server on a namespace by
 providing its in the ``emit()`` call::
diff --git a/docs/intro.rst b/docs/intro.rst
index e05b626..7e862d6 100644
--- a/docs/intro.rst
+++ b/docs/intro.rst
@@ -67,7 +67,7 @@ asynchronous server:
     import eventlet
 
     sio = socketio.Server()
-    app = socketio.WSGIApp(eio, static_files={
+    app = socketio.WSGIApp(sio, static_files={
         '/': {'content_type': 'text/html', 'filename': 'index.html'}
     })
 
@@ -125,7 +125,7 @@ Uvicorn web server:
 Server Features
 ---------------
 
-- Can connect to servers running other complaint Socket.IO clients besides
+- Can connect to servers running other compliant Socket.IO clients besides
   the one in this package.
 - Compatible with Python 2.7 and Python 3.5+.
 - Two versions of the server, one for standard Python and another for
diff --git a/socketio/__init__.py b/socketio/__init__.py
index 6ede89c..96e24d4 100644
--- a/socketio/__init__.py
+++ b/socketio/__init__.py
@@ -24,7 +24,7 @@ else:  # pragma: no cover
     AsyncNamespace = None
     AsyncRedisManager = None
 
-__version__ = '3.1.1'
+__version__ = '3.1.2'
 
 __all__ = ['__version__', 'Client', 'Server', 'BaseManager', 'PubSubManager',
            'KombuManager', 'RedisManager', 'ZmqManager', 'Namespace',
diff --git a/socketio/asyncio_client.py b/socketio/asyncio_client.py
index 2f78a52..88a6e27 100644
--- a/socketio/asyncio_client.py
+++ b/socketio/asyncio_client.py
@@ -162,7 +162,8 @@ class AsyncClient(client.Client):
             packet.EVENT, namespace=namespace, data=[event] + data, id=id,
             binary=binary))
 
-    async def send(self, data, namespace=None, callback=None):
+    async def send(self, data, namespace=None, callback=None, wait=False,
+                   timeout=60):
         """Send a message to one or more connected clients.
 
         This function emits an event with the name ``'message'``. Use
@@ -179,11 +180,55 @@ class AsyncClient(client.Client):
                          that will be passed to the function are those provided
                          by the client. Callback functions can only be used
                          when addressing an individual client.
+        :param wait: If set to ``True``, this function will wait for the
+                     server to handle the event and acknowledge it via its
+                     callback function. The value(s) passed by the server to
+                     its callback will be returned. If set to ``False``,
+                     this function emits the event and returns immediately.
+        :param timeout: If ``wait`` is set to ``True``, this parameter
+                        specifies a waiting timeout. If the timeout is reached
+                        before the server acknowledges the event, then a
+                        ``TimeoutError`` exception is raised.
 
         Note: this method is a coroutine.
         """
         await self.emit('message', data=data, namespace=namespace,
-                        callback=callback)
+                        callback=callback, wait=wait, timeout=timeout)
+
+    async def call(self, event, data=None, namespace=None, timeout=60):
+        """Emit a custom event to a client and wait for the response.
+
+        :param event: The event name. It can be any string. The event names
+                      ``'connect'``, ``'message'`` and ``'disconnect'`` are
+                      reserved and should not be used.
+        :param data: The data to send to the client or clients. Data can be of
+                     type ``str``, ``bytes``, ``list`` or ``dict``. If a
+                     ``list`` or ``dict``, the data will be serialized as JSON.
+        :param namespace: The Socket.IO namespace for the event. If this
+                          argument is omitted the event is emitted to the
+                          default namespace.
+        :param timeout: The waiting timeout. If the timeout is reached before
+                        the client acknowledges the event, then a
+                        ``TimeoutError`` exception is raised.
+
+        Note: this method is a coroutine.
+        """
+        callback_event = self.eio.create_event()
+        callback_args = []
+
+        def event_callback(*args):
+            callback_args.append(args)
+            callback_event.set()
+
+        await self.emit(event, data=data, namespace=namespace,
+                        callback=event_callback)
+        try:
+            await asyncio.wait_for(callback_event.wait(), timeout)
+        except asyncio.TimeoutError:
+            six.raise_from(exceptions.TimeoutError(), None)
+        return callback_args[0] if len(callback_args[0]) > 1 \
+            else callback_args[0][0] if len(callback_args[0]) == 1 \
+                else None
 
     async def disconnect(self):
         """Disconnect from the server.
diff --git a/socketio/asyncio_server.py b/socketio/asyncio_server.py
index f0e4679..b58ab91 100644
--- a/socketio/asyncio_server.py
+++ b/socketio/asyncio_server.py
@@ -1,6 +1,7 @@
 import asyncio
 
 import engineio
+import six
 
 from . import asyncio_manager
 from . import exceptions
@@ -27,7 +28,7 @@ class AsyncServer(server.Server):
                  versions.
     :param async_handlers: If set to ``True``, event handlers are executed in
                            separate threads. To run handlers synchronously,
-                           set to ``False``. The default is ``False``.
+                           set to ``False``. The default is ``True``.
     :param kwargs: Connection parameters for the underlying Engine.IO server.
 
     The Engine.IO configuration supports the following settings:
@@ -60,7 +61,7 @@ class AsyncServer(server.Server):
                             ``False``.
     """
     def __init__(self, client_manager=None, logger=False, json=None,
-                 async_handlers=False, **kwargs):
+                 async_handlers=True, **kwargs):
         if client_manager is None:
             client_manager = asyncio_manager.AsyncManager()
         super().__init__(client_manager=client_manager, logger=logger,
@@ -113,8 +114,9 @@ class AsyncServer(server.Server):
         namespace = namespace or '/'
         self.logger.info('emitting event "%s" to %s [%s]', event,
                          room or 'all', namespace)
-        await self.manager.emit(event, data, namespace, room, skip_sid,
-                                callback, **kwargs)
+        await self.manager.emit(event, data, namespace, room=room,
+                                skip_sid=skip_sid, callback=callback,
+                                **kwargs)
 
     async def send(self, data, room=None, skip_sid=None, namespace=None,
                    callback=None, **kwargs):
@@ -152,9 +154,54 @@ class AsyncServer(server.Server):
 
         Note: this method is a coroutine.
         """
-        await self.emit('message', data, room, skip_sid, namespace, callback,
-                        **kwargs)
+        await self.emit('message', data=data, room=room, skip_sid=skip_sid,
+                        namespace=namespace, callback=callback, **kwargs)
 
+    async def call(self, event, data=None, sid=None, namespace=None,
+                   timeout=60, **kwargs):
+        """Emit a custom event to a client and wait for the response.
+
+        :param event: The event name. It can be any string. The event names
+                      ``'connect'``, ``'message'`` and ``'disconnect'`` are
+                      reserved and should not be used.
+        :param data: The data to send to the client or clients. Data can be of
+                     type ``str``, ``bytes``, ``list`` or ``dict``. If a
+                     ``list`` or ``dict``, the data will be serialized as JSON.
+        :param sid: The session ID of the recipient client.
+        :param namespace: The Socket.IO namespace for the event. If this
+                          argument is omitted the event is emitted to the
+                          default namespace.
+        :param timeout: The waiting timeout. If the timeout is reached before
+                        the client acknowledges the event, then a
+                        ``TimeoutError`` exception is raised.
+        :param ignore_queue: Only used when a message queue is configured. If
+                             set to ``True``, the event is emitted to the
+                             client directly, without going through the queue.
+                             This is more efficient, but only works when a
+                             single server process is used. It is recommended
+                             to always leave this parameter with its default
+                             value of ``False``.
+        """
+        if not self.async_handlers:
+            raise RuntimeError(
+                'Cannot use call() when async_handlers is False.')
+        callback_event = self.eio.create_event()
+        callback_args = []
+
+        def event_callback(*args):
+            callback_args.append(args)
+            callback_event.set()
+        
+        await self.emit(event, data=data, room=sid, namespace=namespace,
+                        callback=event_callback, **kwargs)
+        try:
+            await asyncio.wait_for(callback_event.wait(), timeout)
+        except asyncio.TimeoutError:
+            six.raise_from(exceptions.TimeoutError(), None)
+        return callback_args[0] if len(callback_args[0]) > 1 \
+            else callback_args[0][0] if len(callback_args[0]) == 1 \
+                else None
+    
     async def close_room(self, room, namespace=None):
         """Close a room.
 
diff --git a/socketio/client.py b/socketio/client.py
index f56493f..84e13ef 100644
--- a/socketio/client.py
+++ b/socketio/client.py
@@ -264,7 +264,8 @@ class Client(object):
                                         data=[event] + data, id=id,
                                         binary=binary))
 
-    def send(self, data, namespace=None, callback=None):
+    def send(self, data, namespace=None, callback=None, wait=False,
+             timeout=60):
         """Send a message to one or more connected clients.
 
         This function emits an event with the name ``'message'``. Use
@@ -281,9 +282,49 @@ class Client(object):
                          that will be passed to the function are those provided
                          by the client. Callback functions can only be used
                          when addressing an individual client.
+        :param wait: If set to ``True``, this function will wait for the
+                     server to handle the event and acknowledge it via its
+                     callback function. The value(s) passed by the server to
+                     its callback will be returned. If set to ``False``,
+                     this function emits the event and returns immediately.
+        :param timeout: If ``wait`` is set to ``True``, this parameter
+                        specifies a waiting timeout. If the timeout is reached
+                        before the server acknowledges the event, then a
+                        ``TimeoutError`` exception is raised.
         """
         self.emit('message', data=data, namespace=namespace,
-                  callback=callback)
+                  callback=callback, wait=wait, timeout=timeout)
+
+    def call(self, event, data=None, namespace=None, timeout=60):
+        """Emit a custom event to a client and wait for the response.
+
+        :param event: The event name. It can be any string. The event names
+                      ``'connect'``, ``'message'`` and ``'disconnect'`` are
+                      reserved and should not be used.
+        :param data: The data to send to the client or clients. Data can be of
+                     type ``str``, ``bytes``, ``list`` or ``dict``. If a
+                     ``list`` or ``dict``, the data will be serialized as JSON.
+        :param namespace: The Socket.IO namespace for the event. If this
+                          argument is omitted the event is emitted to the
+                          default namespace.
+        :param timeout: The waiting timeout. If the timeout is reached before
+                        the client acknowledges the event, then a
+                        ``TimeoutError`` exception is raised.
+        """
+        callback_event = self.eio.create_event()
+        callback_args = []
+
+        def event_callback(*args):
+            callback_args.append(args)
+            callback_event.set()
+        
+        self.emit(event, data=data, namespace=namespace,
+                  callback=event_callback)
+        if not callback_event.wait(timeout=timeout):
+            raise exceptions.TimeoutError()
+        return callback_args[0] if len(callback_args[0]) > 1 \
+            else callback_args[0][0] if len(callback_args[0]) == 1 \
+                else None
 
     def disconnect(self):
         """Disconnect from the server."""
diff --git a/socketio/exceptions.py b/socketio/exceptions.py
index 2c325f2..ded2be1 100644
--- a/socketio/exceptions.py
+++ b/socketio/exceptions.py
@@ -5,7 +5,7 @@ class SocketIOError(Exception):
 class ConnectionError(SocketIOError):
     pass
 
-
+ 
 class ConnectionRefusedError(ConnectionError):
     """
     Raised when connection is refused on the application level
@@ -18,3 +18,7 @@ class ConnectionRefusedError(ConnectionError):
         This method could be overridden in subclass to add extra logic for data output
         """
         return self._info
+
+      
+class TimeoutError(SocketIOError):
+    pass
diff --git a/socketio/server.py b/socketio/server.py
index 8151e53..14707bb 100644
--- a/socketio/server.py
+++ b/socketio/server.py
@@ -5,8 +5,8 @@ import six
 
 from . import base_manager
 from . import exceptions
-from . import packet
 from . import namespace
+from . import packet
 
 default_logger = logging.getLogger('socketio.server')
 
@@ -34,9 +34,10 @@ class Server(object):
                  packets. Custom json modules must have ``dumps`` and ``loads``
                  functions that are compatible with the standard library
                  versions.
-    :param async_handlers: If set to ``True``, event handlers are executed in
-                           separate threads. To run handlers synchronously,
-                           set to ``False``. The default is ``False``.
+    :param async_handlers: If set to ``True``, event handlers for a client are
+                           executed in separate threads. To run handlers for a
+                           client synchronously, set to ``False``. The default
+                           is ``True``.
     :param kwargs: Connection parameters for the underlying Engine.IO server.
 
     The Engine.IO configuration supports the following settings:
@@ -78,7 +79,7 @@ class Server(object):
                             ``False``. The default is ``False``.
     """
     def __init__(self, client_manager=None, logger=False, binary=False,
-                 json=None, async_handlers=False, **kwargs):
+                 json=None, async_handlers=True, **kwargs):
         engineio_options = kwargs
         engineio_logger = engineio_options.pop('engineio_logger', None)
         if engineio_logger is not None:
@@ -225,11 +226,11 @@ class Server(object):
         namespace = namespace or '/'
         self.logger.info('emitting event "%s" to %s [%s]', event,
                          room or 'all', namespace)
-        self.manager.emit(event, data, namespace, room, skip_sid, callback,
-                          **kwargs)
+        self.manager.emit(event, data, namespace, room=room,
+                          skip_sid=skip_sid, callback=callback, **kwargs)
 
     def send(self, data, room=None, skip_sid=None, namespace=None,
-             callback=None, **kwargs):
+             callback=None, wait=False, timeout=60, **kwargs):
         """Send a message to one or more connected clients.
 
         This function emits an event with the name ``'message'``. Use
@@ -262,8 +263,51 @@ class Server(object):
                              to always leave this parameter with its default
                              value of ``False``.
         """
-        self.emit('message', data, room, skip_sid, namespace, callback,
-                  **kwargs)
+        self.emit('message', data=data, room=room, skip_sid=skip_sid,
+                  namespace=namespace, callback=callback, **kwargs)
+
+    def call(self, event, data=None, sid=None, namespace=None, timeout=60,
+             **kwargs):
+        """Emit a custom event to a client and wait for the response.
+
+        :param event: The event name. It can be any string. The event names
+                      ``'connect'``, ``'message'`` and ``'disconnect'`` are
+                      reserved and should not be used.
+        :param data: The data to send to the client or clients. Data can be of
+                     type ``str``, ``bytes``, ``list`` or ``dict``. If a
+                     ``list`` or ``dict``, the data will be serialized as JSON.
+        :param sid: The session ID of the recipient client.
+        :param namespace: The Socket.IO namespace for the event. If this
+                          argument is omitted the event is emitted to the
+                          default namespace.
+        :param timeout: The waiting timeout. If the timeout is reached before
+                        the client acknowledges the event, then a
+                        ``TimeoutError`` exception is raised.
+        :param ignore_queue: Only used when a message queue is configured. If
+                             set to ``True``, the event is emitted to the
+                             client directly, without going through the queue.
+                             This is more efficient, but only works when a
+                             single server process is used. It is recommended
+                             to always leave this parameter with its default
+                             value of ``False``.
+        """
+        if not self.async_handlers:
+            raise RuntimeError(
+                'Cannot use call() when async_handlers is False.')
+        callback_event = self.eio.create_event()
+        callback_args = []
+
+        def event_callback(*args):
+            callback_args.append(args)
+            callback_event.set()
+        
+        self.emit(event, data=data, room=sid, namespace=namespace,
+                  callback=event_callback, **kwargs)
+        if not callback_event.wait(timeout=timeout):
+            raise exceptions.TimeoutError()
+        return callback_args[0] if len(callback_args[0]) > 1 \
+            else callback_args[0][0] if len(callback_args[0]) == 1 \
+                else None
 
     def enter_room(self, sid, room, namespace=None):
         """Enter a room.
diff --git a/tests/asyncio/test_asyncio_client.py b/tests/asyncio/test_asyncio_client.py
index 78bca0f..3114443 100644
--- a/tests/asyncio/test_asyncio_client.py
+++ b/tests/asyncio/test_asyncio_client.py
@@ -240,14 +240,50 @@ class TestAsyncClient(unittest.TestCase):
         _run(c.send('data', 'namespace', 'callback'))
         c.emit.mock.assert_called_once_with(
             'message', data='data', namespace='namespace',
-            callback='callback')
+            callback='callback', wait=False, timeout=60)
 
     def test_send_with_defaults(self):
         c = asyncio_client.AsyncClient()
         c.emit = AsyncMock()
         _run(c.send('data'))
         c.emit.mock.assert_called_once_with(
-            'message', data='data', namespace=None, callback=None)
+            'message', data='data', namespace=None, callback=None, wait=False,
+            timeout=60)
+
+    def test_call(self):
+        c = asyncio_client.AsyncClient()
+
+        async def fake_event_wait():
+            c._generate_ack_id.call_args_list[0][0][1]('foo', 321)
+
+        c._send_packet = AsyncMock()
+        c._generate_ack_id = mock.MagicMock(return_value=123)
+        c.eio = mock.MagicMock()
+        c.eio.create_event.return_value.wait = fake_event_wait
+        self.assertEqual(_run(c.call('foo')), ('foo', 321))
+        expected_packet = packet.Packet(packet.EVENT, namespace='/',
+                                        data=['foo'], id=123, binary=False)
+        self.assertEqual(c._send_packet.mock.call_count, 1)
+        self.assertEqual(c._send_packet.mock.call_args_list[0][0][0].encode(),
+                         expected_packet.encode())
+
+    def test_call_with_timeout(self):
+        c = asyncio_client.AsyncClient()
+
+        async def fake_event_wait():
+            await asyncio.sleep(1)
+
+        c._send_packet = AsyncMock()
+        c._generate_ack_id = mock.MagicMock(return_value=123)
+        c.eio = mock.MagicMock()
+        c.eio.create_event.return_value.wait = fake_event_wait
+        self.assertRaises(exceptions.TimeoutError, _run,
+                          c.call('foo', timeout=0.01))
+        expected_packet = packet.Packet(packet.EVENT, namespace='/',
+                                        data=['foo'], id=123, binary=False)
+        self.assertEqual(c._send_packet.mock.call_count, 1)
+        self.assertEqual(c._send_packet.mock.call_args_list[0][0][0].encode(),
+                         expected_packet.encode())
 
     def test_disconnect(self):
         c = asyncio_client.AsyncClient()
diff --git a/tests/asyncio/test_asyncio_server.py b/tests/asyncio/test_asyncio_server.py
index 4a8f00c..5726b93 100644
--- a/tests/asyncio/test_asyncio_server.py
+++ b/tests/asyncio/test_asyncio_server.py
@@ -12,8 +12,9 @@ else:
 
 from socketio import asyncio_server, exceptions
 from socketio import asyncio_namespace
-from socketio import packet
+from socketio import exceptions
 from socketio import namespace
+from socketio import packet
 
 
 def AsyncMock(*args, **kwargs):
@@ -83,24 +84,57 @@ class TestAsyncServer(unittest.TestCase):
     def test_emit(self, eio):
         mgr = self._get_mock_manager()
         s = asyncio_server.AsyncServer(client_manager=mgr)
-        _run(s.emit('my event', {'foo': 'bar'}, 'room', '123',
-                    namespace='/foo', callback='cb'))
+        _run(s.emit('my event', {'foo': 'bar'}, room='room',
+                    skip_sid='123', namespace='/foo', callback='cb'))
         s.manager.emit.mock.assert_called_once_with(
-            'my event', {'foo': 'bar'}, '/foo', 'room', '123', 'cb')
+            'my event', {'foo': 'bar'}, '/foo', room='room', skip_sid='123',
+            callback='cb')
 
     def test_emit_default_namespace(self, eio):
         mgr = self._get_mock_manager()
         s = asyncio_server.AsyncServer(client_manager=mgr)
-        _run(s.emit('my event', {'foo': 'bar'}, 'room', '123', callback='cb'))
-        s.manager.emit.mock.assert_called_once_with('my event', {'foo': 'bar'},
-                                                    '/', 'room', '123', 'cb')
+        _run(s.emit('my event', {'foo': 'bar'}, room='room',
+                    skip_sid='123', callback='cb'))
+        s.manager.emit.mock.assert_called_once_with(
+            'my event', {'foo': 'bar'}, '/', room='room', skip_sid='123',
+            callback='cb')
 
     def test_send(self, eio):
         mgr = self._get_mock_manager()
         s = asyncio_server.AsyncServer(client_manager=mgr)
         _run(s.send('foo', 'room', '123', namespace='/foo', callback='cb'))
-        s.manager.emit.mock.assert_called_once_with('message', 'foo', '/foo',
-                                                    'room', '123', 'cb')
+        s.manager.emit.mock.assert_called_once_with(
+            'message', 'foo', '/foo', room='room', skip_sid='123',
+            callback='cb')
+
+    def test_call(self, eio):
+        mgr = self._get_mock_manager()
+        s = asyncio_server.AsyncServer(client_manager=mgr)
+
+        async def fake_event_wait():
+            s.manager.emit.mock.call_args_list[0][1]['callback']('foo', 321)
+            return True
+
+        s.eio.create_event.return_value.wait = fake_event_wait
+        self.assertEqual(_run(s.call('foo', sid='123')), ('foo', 321))
+
+    def test_call_with_timeout(self, eio):
+        mgr = self._get_mock_manager()
+        s = asyncio_server.AsyncServer(client_manager=mgr)
+
+        async def fake_event_wait():
+            await asyncio.sleep(1)
+
+        s.eio.create_event.return_value.wait = fake_event_wait
+        self.assertRaises(exceptions.TimeoutError, _run,
+                          s.call('foo', sid='123', timeout=0.01))
+
+    def test_call_without_async_handlers(self, eio):
+        mgr = self._get_mock_manager()
+        s = asyncio_server.AsyncServer(client_manager=mgr,
+                                       async_handlers=False)
+        self.assertRaises(RuntimeError, _run,
+            s.call('foo', sid='123', timeout=12))
 
     def test_enter_room(self, eio):
         mgr = self._get_mock_manager()
@@ -357,7 +391,7 @@ class TestAsyncServer(unittest.TestCase):
 
     def test_handle_event(self, eio):
         eio.return_value.send = AsyncMock()
-        s = asyncio_server.AsyncServer()
+        s = asyncio_server.AsyncServer(async_handlers=False)
         handler = AsyncMock()
         s.on('my message', handler)
         _run(s._handle_eio_message('123', '2["my message","a","b","c"]'))
@@ -365,7 +399,7 @@ class TestAsyncServer(unittest.TestCase):
 
     def test_handle_event_with_namespace(self, eio):
         eio.return_value.send = AsyncMock()
-        s = asyncio_server.AsyncServer()
+        s = asyncio_server.AsyncServer(async_handlers=False)
         handler = mock.MagicMock()
         s.on('my message', handler, namespace='/foo')
         _run(s._handle_eio_message('123', '2/foo,["my message","a","b","c"]'))
@@ -373,7 +407,7 @@ class TestAsyncServer(unittest.TestCase):
 
     def test_handle_event_binary(self, eio):
         eio.return_value.send = AsyncMock()
-        s = asyncio_server.AsyncServer()
+        s = asyncio_server.AsyncServer(async_handlers=False)
         handler = mock.MagicMock()
         s.on('my message', handler)
         _run(s._handle_eio_message('123', '52-["my message","a",'
@@ -386,7 +420,7 @@ class TestAsyncServer(unittest.TestCase):
     def test_handle_event_binary_ack(self, eio):
         eio.return_value.send = AsyncMock()
         mgr = self._get_mock_manager()
-        s = asyncio_server.AsyncServer(client_manager=mgr)
+        s = asyncio_server.AsyncServer(client_manager=mgr, async_handlers=False)
         s.manager.initialize(s)
         _run(s._handle_eio_message('123', '61-321["my message","a",'
                                           '{"_placeholder":true,"num":0}]'))
@@ -396,7 +430,7 @@ class TestAsyncServer(unittest.TestCase):
 
     def test_handle_event_with_ack(self, eio):
         eio.return_value.send = AsyncMock()
-        s = asyncio_server.AsyncServer()
+        s = asyncio_server.AsyncServer(async_handlers=False)
         handler = mock.MagicMock(return_value='foo')
         s.on('my message', handler)
         _run(s._handle_eio_message('123', '21000["my message","foo"]'))
@@ -406,7 +440,7 @@ class TestAsyncServer(unittest.TestCase):
 
     def test_handle_event_with_ack_none(self, eio):
         eio.return_value.send = AsyncMock()
-        s = asyncio_server.AsyncServer()
+        s = asyncio_server.AsyncServer(async_handlers=False)
         handler = mock.MagicMock(return_value=None)
         s.on('my message', handler)
         _run(s._handle_eio_message('123', '21000["my message","foo"]'))
@@ -417,7 +451,7 @@ class TestAsyncServer(unittest.TestCase):
     def test_handle_event_with_ack_tuple(self, eio):
         eio.return_value.send = AsyncMock()
         mgr = self._get_mock_manager()
-        s = asyncio_server.AsyncServer(client_manager=mgr)
+        s = asyncio_server.AsyncServer(client_manager=mgr, async_handlers=False)
         handler = mock.MagicMock(return_value=(1, '2', True))
         s.on('my message', handler)
         _run(s._handle_eio_message('123', '21000["my message","a","b","c"]'))
@@ -428,7 +462,7 @@ class TestAsyncServer(unittest.TestCase):
     def test_handle_event_with_ack_list(self, eio):
         eio.return_value.send = AsyncMock()
         mgr = self._get_mock_manager()
-        s = asyncio_server.AsyncServer(client_manager=mgr)
+        s = asyncio_server.AsyncServer(client_manager=mgr, async_handlers=False)
         handler = mock.MagicMock(return_value=[1, '2', True])
         s.on('my message', handler)
         _run(s._handle_eio_message('123', '21000["my message","a","b","c"]'))
@@ -439,7 +473,7 @@ class TestAsyncServer(unittest.TestCase):
     def test_handle_event_with_ack_binary(self, eio):
         eio.return_value.send = AsyncMock()
         mgr = self._get_mock_manager()
-        s = asyncio_server.AsyncServer(client_manager=mgr)
+        s = asyncio_server.AsyncServer(client_manager=mgr, async_handlers=False)
         handler = mock.MagicMock(return_value=b'foo')
         s.on('my message', handler)
         _run(s._handle_eio_message('123', '21000["my message","foo"]'))
@@ -566,7 +600,7 @@ class TestAsyncServer(unittest.TestCase):
             async def on_baz(self, sid, data1, data2):
                 result['result'] = (data1, data2)
 
-        s = asyncio_server.AsyncServer()
+        s = asyncio_server.AsyncServer(async_handlers=False)
         s.register_namespace(MyNamespace('/foo'))
         _run(s._handle_eio_connect('123', 'environ'))
         _run(s._handle_eio_message('123', '0/foo'))
diff --git a/tests/common/test_client.py b/tests/common/test_client.py
index 02d5ed0..8fd078d 100644
--- a/tests/common/test_client.py
+++ b/tests/common/test_client.py
@@ -323,14 +323,53 @@ class TestClient(unittest.TestCase):
         c.send('data', 'namespace', 'callback')
         c.emit.assert_called_once_with(
             'message', data='data', namespace='namespace',
-            callback='callback')
+            callback='callback', wait=False, timeout=60)
 
     def test_send_with_defaults(self):
         c = client.Client()
         c.emit = mock.MagicMock()
         c.send('data')
         c.emit.assert_called_once_with(
-            'message', data='data', namespace=None, callback=None)
+            'message', data='data', namespace=None, callback=None, wait=False,
+            timeout=60)
+
+    def test_call(self):
+        c = client.Client()
+
+        def fake_event_wait(timeout=None):
+            self.assertEqual(timeout, 60)
+            c._generate_ack_id.call_args_list[0][0][1]('foo', 321)
+            return True
+
+        c._send_packet = mock.MagicMock()
+        c._generate_ack_id = mock.MagicMock(return_value=123)
+        c.eio = mock.MagicMock()
+        c.eio.create_event.return_value.wait = fake_event_wait
+        self.assertEqual(c.call('foo'), ('foo', 321))
+        expected_packet = packet.Packet(packet.EVENT, namespace='/',
+                                        data=['foo'], id=123, binary=False)
+        self.assertEqual(c._send_packet.call_count, 1)
+        self.assertEqual(c._send_packet.call_args_list[0][0][0].encode(),
+                         expected_packet.encode())
+
+    def test_call_with_timeout(self):
+        c = client.Client()
+
+        def fake_event_wait(timeout=None):
+            self.assertEqual(timeout, 12)
+            return False
+
+        c._send_packet = mock.MagicMock()
+        c._generate_ack_id = mock.MagicMock(return_value=123)
+        c.eio = mock.MagicMock()
+        c.eio.create_event.return_value.wait = fake_event_wait
+        self.assertRaises(exceptions.TimeoutError, c.call, 'foo',
+                          timeout=12)
+        expected_packet = packet.Packet(packet.EVENT, namespace='/',
+                                        data=['foo'], id=123, binary=False)
+        self.assertEqual(c._send_packet.call_count, 1)
+        self.assertEqual(c._send_packet.call_args_list[0][0][0].encode(),
+                         expected_packet.encode())
 
     def test_disconnect(self):
         c = client.Client()
diff --git a/tests/common/test_server.py b/tests/common/test_server.py
index 61df07d..533989a 100644
--- a/tests/common/test_server.py
+++ b/tests/common/test_server.py
@@ -9,9 +9,9 @@ else:
     import mock
 
 from socketio import exceptions
+from socketio import namespace
 from socketio import packet
 from socketio import server
-from socketio import namespace
 
 
 @mock.patch('engineio.Server')
@@ -53,22 +53,55 @@ class TestServer(unittest.TestCase):
         s = server.Server(client_manager=mgr)
         s.emit('my event', {'foo': 'bar'}, 'room', '123', namespace='/foo',
                callback='cb')
-        s.manager.emit.assert_called_once_with('my event', {'foo': 'bar'},
-                                               '/foo', 'room', '123', 'cb')
+        s.manager.emit.assert_called_once_with(
+            'my event', {'foo': 'bar'}, '/foo', room='room', skip_sid='123',
+            callback='cb')
 
     def test_emit_default_namespace(self, eio):
         mgr = mock.MagicMock()
         s = server.Server(client_manager=mgr)
         s.emit('my event', {'foo': 'bar'}, 'room', '123', callback='cb')
-        s.manager.emit.assert_called_once_with('my event', {'foo': 'bar'}, '/',
-                                               'room', '123', 'cb')
+        s.manager.emit.assert_called_once_with(
+            'my event', {'foo': 'bar'}, '/', room='room', skip_sid='123',
+            callback='cb')
 
     def test_send(self, eio):
         mgr = mock.MagicMock()
         s = server.Server(client_manager=mgr)
         s.send('foo', 'room', '123', namespace='/foo', callback='cb')
-        s.manager.emit.assert_called_once_with('message', 'foo', '/foo',
-                                               'room', '123', 'cb')
+        s.manager.emit.assert_called_once_with(
+            'message', 'foo', '/foo', room='room', skip_sid='123',
+            callback='cb')
+
+    def test_call(self, eio):
+        mgr = mock.MagicMock()
+        s = server.Server(client_manager=mgr)
+
+        def fake_event_wait(timeout=None):
+            self.assertEqual(timeout, 60)
+            s.manager.emit.call_args_list[0][1]['callback']('foo', 321)
+            return True
+
+        s.eio.create_event.return_value.wait = fake_event_wait
+        self.assertEqual(s.call('foo', sid='123'), ('foo', 321))
+
+    def test_call_with_timeout(self, eio):
+        mgr = mock.MagicMock()
+        s = server.Server(client_manager=mgr)
+
+        def fake_event_wait(timeout=None):
+            self.assertEqual(timeout, 12)
+            return False
+
+        s.eio.create_event.return_value.wait = fake_event_wait
+        self.assertRaises(exceptions.TimeoutError, s.call, 'foo',
+                          sid='123', timeout=12)
+
+    def test_call_without_async_handlers(self, eio):
+        mgr = mock.MagicMock()
+        s = server.Server(client_manager=mgr, async_handlers=False)
+        self.assertRaises(RuntimeError, s.call, 'foo',
+                          sid='123', timeout=12)
 
     def test_enter_room(self, eio):
         mgr = mock.MagicMock()
@@ -292,21 +325,21 @@ class TestServer(unittest.TestCase):
         s._handle_eio_disconnect('123')
 
     def test_handle_event(self, eio):
-        s = server.Server()
+        s = server.Server(async_handlers=False)
         handler = mock.MagicMock()
         s.on('my message', handler)
         s._handle_eio_message('123', '2["my message","a","b","c"]')
         handler.assert_called_once_with('123', 'a', 'b', 'c')
 
     def test_handle_event_with_namespace(self, eio):
-        s = server.Server()
+        s = server.Server(async_handlers=False)
         handler = mock.MagicMock()
         s.on('my message', handler, namespace='/foo')
         s._handle_eio_message('123', '2/foo,["my message","a","b","c"]')
         handler.assert_called_once_with('123', 'a', 'b', 'c')
 
     def test_handle_event_binary(self, eio):
-        s = server.Server()
+        s = server.Server(async_handlers=False)
         handler = mock.MagicMock()
         s.on('my message', handler)
         s._handle_eio_message('123', '52-["my message","a",'
@@ -327,7 +360,7 @@ class TestServer(unittest.TestCase):
             '123', '/', 321, ['my message', 'a', b'foo'])
 
     def test_handle_event_with_ack(self, eio):
-        s = server.Server()
+        s = server.Server(async_handlers=False)
         handler = mock.MagicMock(return_value='foo')
         s.on('my message', handler)
         s._handle_eio_message('123', '21000["my message","foo"]')
@@ -336,7 +369,7 @@ class TestServer(unittest.TestCase):
                                            binary=False)
 
     def test_handle_event_with_ack_none(self, eio):
-        s = server.Server()
+        s = server.Server(async_handlers=False)
         handler = mock.MagicMock(return_value=None)
         s.on('my message', handler)
         s._handle_eio_message('123', '21000["my message","foo"]')
@@ -346,7 +379,7 @@ class TestServer(unittest.TestCase):
 
     def test_handle_event_with_ack_tuple(self, eio):
         mgr = mock.MagicMock()
-        s = server.Server(client_manager=mgr)
+        s = server.Server(client_manager=mgr, async_handlers=False)
         handler = mock.MagicMock(return_value=(1, '2', True))
         s.on('my message', handler)
         s._handle_eio_message('123', '21000["my message","a","b","c"]')
@@ -356,7 +389,7 @@ class TestServer(unittest.TestCase):
 
     def test_handle_event_with_ack_list(self, eio):
         mgr = mock.MagicMock()
-        s = server.Server(client_manager=mgr)
+        s = server.Server(client_manager=mgr, async_handlers=False)
         handler = mock.MagicMock(return_value=[1, '2', True])
         s.on('my message', handler)
         s._handle_eio_message('123', '21000["my message","a","b","c"]')
@@ -366,7 +399,7 @@ class TestServer(unittest.TestCase):
 
     def test_handle_event_with_ack_binary(self, eio):
         mgr = mock.MagicMock()
-        s = server.Server(client_manager=mgr, binary=True)
+        s = server.Server(client_manager=mgr, binary=True, async_handlers=False)
         handler = mock.MagicMock(return_value=b'foo')
         s.on('my message', handler)
         s._handle_eio_message('123', '21000["my message","foo"]')
@@ -479,7 +512,7 @@ class TestServer(unittest.TestCase):
             def on_baz(self, sid, data1, data2):
                 result['result'] = (data1, data2)
 
-        s = server.Server()
+        s = server.Server(async_handlers=False)
         s.register_namespace(MyNamespace('/foo'))
         s._handle_eio_connect('123', 'environ')
         s._handle_eio_message('123', '0/foo')