diff --git a/src/Network/WebSockets/Simple.hs b/src/Network/WebSockets/Simple.hs
--- a/src/Network/WebSockets/Simple.hs
+++ b/src/Network/WebSockets/Simple.hs
@@ -9,12 +9,13 @@
 
 module Network.WebSockets.Simple where
 
-import Network.WebSockets (DataMessage (..), sendTextData, receiveDataMessage, acceptRequest, ConnectionException)
+import Network.WebSockets (DataMessage (..), sendTextData, sendClose, receiveDataMessage, acceptRequest, ConnectionException (CloseRequest))
 import Network.Wai.Trans (ServerAppT, ClientAppT)
 import Data.Aeson (ToJSON (..), FromJSON (..))
 import qualified Data.Aeson as Aeson
 import Data.ByteString.Lazy (ByteString)
 import Data.IORef (newIORef, writeIORef, readIORef)
+import Data.Word (Word16)
 
 import Control.Monad (void, forever)
 import Control.Monad.Catch (Exception, throwM, MonadThrow, catch, MonadCatch)
@@ -28,9 +29,17 @@
 import Data.Typeable (Typeable)
 
 
+
+data WebSocketsAppParams send m = WebSocketsAppParams
+  { send  :: send -> m ()
+  , close :: m ()
+  } deriving (Generic, Typeable)
+
+
 data WebSocketsApp send receive m = WebSocketsApp
-  { onOpen    :: (send -> m ()) -> m ()
-  , onReceive :: (send -> m ()) -> receive -> m ()
+  { onOpen    :: WebSocketsAppParams send m -> m ()
+  , onReceive :: WebSocketsAppParams send m -> receive -> m ()
+  , onClose   :: Maybe (Word16, ByteString) -> m () -- ^ Either was a clean close, with 'Network.WebSockets.CloseRequest' params, or was unclean
   } deriving (Generic, Typeable)
 
 
@@ -38,9 +47,10 @@
                    -> (forall a. n a -> m a)
                    -> WebSocketsApp send receive m
                    -> WebSocketsApp send receive n
-hoistWebSocketsApp f coF WebSocketsApp{onOpen,onReceive} = WebSocketsApp
-  { onOpen = \send -> f $ onOpen (coF . send)
-  , onReceive = \send r -> f $ onReceive (coF . send) r
+hoistWebSocketsApp f coF WebSocketsApp{onOpen,onReceive,onClose} = WebSocketsApp
+  { onOpen = \WebSocketsAppParams{send,close} -> f $ onOpen WebSocketsAppParams{send = coF . send, close = coF close}
+  , onReceive = \WebSocketsAppParams{send,close} r -> f $ onReceive WebSocketsAppParams{send = coF . send, close = coF close} r
+  , onClose = f . onClose
   }
 
 
@@ -57,7 +67,7 @@
                 )
              => WebSocketsApp send receive m
              -> ClientAppT m (Maybe WebSocketsAppThreads)
-toClientAppT WebSocketsApp{onOpen,onReceive} conn = do
+toClientAppT WebSocketsApp{onOpen,onReceive,onClose} conn = do
   toWaitVar <- liftBaseWith $ \_ -> newIORef (0 :: Int)
   let go =
         let go' = do
@@ -65,8 +75,14 @@
               let send :: send -> m ()
                   send x = liftBaseWith $ \_ -> sendTextData conn (Aeson.encode x)
 
+                  close :: m ()
+                  close = liftBaseWith $ \_ -> sendClose conn (Aeson.encode "requesting close")
+
+                  params :: WebSocketsAppParams send m
+                  params = WebSocketsAppParams{send,close}
+
               onOpenThread <- liftBaseWith $ \runToBase ->
-                async $ void $ runToBase $ onOpen send
+                async $ void $ runToBase $ onOpen params
 
               onReceiveThreads <- liftBaseWith $ \_ -> newTChanIO
 
@@ -78,7 +94,7 @@
                 case Aeson.decode data'' of
                   Nothing -> throwM (JSONParseError data'')
                   Just received -> liftBaseWith $ \runToBase -> do
-                    thread <- async $ void $ runToBase $ onReceive send received
+                    thread <- async $ void $ runToBase $ onReceive params received
                     atomically $ writeTChan onReceiveThreads thread
 
               pure $ Just WebSocketsAppThreads
@@ -87,7 +103,10 @@
                 }
 
             onDisconnect :: ConnectionException -> m (Maybe WebSocketsAppThreads)
-            onDisconnect _ = do
+            onDisconnect err = do
+              case err of
+                CloseRequest code reason -> onClose (Just (code,reason))
+                _                        -> onClose Nothing
               liftBaseWith $ \_ -> do
                 toWait <- readIORef toWaitVar
                 writeIORef toWaitVar (toWait+1)
diff --git a/src/Network/WebSockets/Simple/PingPong.hs b/src/Network/WebSockets/Simple/PingPong.hs
--- a/src/Network/WebSockets/Simple/PingPong.hs
+++ b/src/Network/WebSockets/Simple/PingPong.hs
@@ -5,7 +5,7 @@
 
 module Network.WebSockets.Simple.PingPong where
 
-import Network.WebSockets.Simple (WebSocketsApp (..))
+import Network.WebSockets.Simple (WebSocketsApp (..), WebSocketsAppParams (..))
 
 import Data.Aeson (ToJSON (..), FromJSON (..))
 import Data.Aeson.Types (Value (Array))
@@ -34,24 +34,25 @@
          => Int -- ^ Delay in microseconds
          -> WebSocketsApp send receive m
          -> m (WebSocketsApp (PingPong send) (PingPong receive) m)
-pingPong delay WebSocketsApp{onOpen,onReceive} = do
+pingPong delay WebSocketsApp{onOpen,onReceive,onClose} = do
   counterVar <- liftBaseWith $ \_ -> newTVarIO Nothing
 
   let halfDelay = delay `div` 2
 
   pure WebSocketsApp
-    { onOpen = \send -> do
+    { onOpen = \WebSocketsAppParams{send,close} -> do
         liftBaseWith $ \runInBase -> do
           counter <- every delay (Just halfDelay) $ runInBase $
             send (PingPong Nothing)
           atomically $ writeTVar counterVar (Just counter)
-        onOpen (send . PingPong . Just)
-    , onReceive = \send (PingPong mPingPong) -> do
+        onOpen WebSocketsAppParams{send = send . PingPong . Just, close}
+    , onReceive = \WebSocketsAppParams{send,close} (PingPong mPingPong) ->
         case mPingPong of
           Nothing -> liftBaseWith $ \_ -> do
             mCounter <- atomically $ readTVar counterVar
             case mCounter of
               Nothing -> error "somehow received message before socket was opened"
               Just counter -> reset (Just halfDelay) counter
-          Just r -> onReceive (send . PingPong . Just) r
+          Just r -> onReceive WebSocketsAppParams{send = send . PingPong . Just, close} r
+    , onClose
     }
diff --git a/websockets-simple.cabal b/websockets-simple.cabal
--- a/websockets-simple.cabal
+++ b/websockets-simple.cabal
@@ -1,5 +1,5 @@
 name:                websockets-simple
-version:             0.0.3
+version:             0.0.4
 synopsis:            Simpler interface to the websockets api
 -- description:
 homepage:            https://github.com/athanclark/websockets-simple#readme