diff --git a/websocket-sharp/Server/HttpServer.cs b/websocket-sharp/Server/HttpServer.cs
index 9966f0dc..360958e5 100644
--- a/websocket-sharp/Server/HttpServer.cs
+++ b/websocket-sharp/Server/HttpServer.cs
@@ -62,12 +62,13 @@ namespace WebSocketSharp.Server {
 
     #region Private Fields
 
-    private bool               _isWindows;
     private HttpListener       _listener;
+    private bool               _listening;
     private int                _port;
     private Thread             _receiveRequestThread;
     private string             _rootPath;
     private ServiceHostManager _svcHosts;
+    private bool               _windows;
 
     #endregion
 
@@ -99,6 +100,18 @@ namespace WebSocketSharp.Server {
 
     #region Public Properties
 
+    /// <summary>
+    /// Gets a value indicating whether the server has been started.
+    /// </summary>
+    /// <value>
+    /// <c>true</c> if the server has been started; otherwise, <c>false</c>.
+    /// </value>
+    public bool IsListening {
+      get {
+        return _listening;
+      }
+    }
+
     /// <summary>
     /// Gets the port on which to listen for incoming requests.
     /// </summary>
@@ -125,7 +138,8 @@ namespace WebSocketSharp.Server {
       }
 
       set {
-        _rootPath = value;
+        if (!_listening)
+          _rootPath = value;
       }
     }
 
@@ -220,18 +234,18 @@ namespace WebSocketSharp.Server {
     private void init()
     {
       _listener = new HttpListener();
+      _listening = false;
+      _rootPath = getRootPath();
       _svcHosts = new ServiceHostManager();
 
-      _isWindows = false;
+      _windows = false;
       var os = Environment.OSVersion;
       if (os.Platform != PlatformID.Unix && os.Platform != PlatformID.MacOSX)
-        _isWindows = true;
+        _windows = true;
 
       var prefix = String.Format(
         "http{0}://*:{1}/", _port == 443 ? "s" : String.Empty, _port);
       _listener.Prefixes.Add(prefix);
-
-      _rootPath = getRootPath();
     }
 
     private static string getRootPath()
@@ -252,7 +266,7 @@ namespace WebSocketSharp.Server {
     {
       #if DEBUG
       var callerFrame = new StackFrame(1);
-      var caller      = callerFrame.GetMethod();
+      var caller = callerFrame.GetMethod();
       Console.WriteLine("HTTPSV: Error@{0}: {1}", caller.Name, message);
       #endif
       OnError.Emit(this, new ErrorEventArgs(message));
@@ -382,9 +396,9 @@ namespace WebSocketSharp.Server {
 
     private bool upgradeToWebSocket(HttpListenerContext context)
     {
-      var res       = context.Response;
+      var res = context.Response;
       var wsContext = context.AcceptWebSocket();
-      var path      = wsContext.Path.UrlDecode();
+      var path = wsContext.Path.UrlDecode();
 
       IServiceHost svcHost;
       if (!_svcHosts.TryGetServiceHost(path, out svcHost))
@@ -441,7 +455,7 @@ namespace WebSocketSharp.Server {
     public byte[] GetFile(string path)
     {
       var filePath = _rootPath + path;
-      if (_isWindows)
+      if (_windows)
         filePath = filePath.Replace("/", "\\");
 
       return File.Exists(filePath)
@@ -450,22 +464,30 @@ namespace WebSocketSharp.Server {
     }
 
     /// <summary>
-    /// Starts the <see cref="HttpServer"/>.
+    /// Starts to receive the HTTP requests.
     /// </summary>
     public void Start()
     {
+      if (_listening)
+        return;
+
       _listener.Start();
       startReceiveRequestThread();
+      _listening = true;
     }
 
     /// <summary>
-    /// Shuts down the <see cref="HttpServer"/>.
+    /// Stops receiving the HTTP requests.
     /// </summary>
     public void Stop()
     {
+      if (!_listening)
+        return;
+
       _listener.Close();
       _receiveRequestThread.Join(5 * 1000);
       _svcHosts.Stop();
+      _listening = false;
     }
 
     #endregion
diff --git a/websocket-sharp/Server/WebSocketServer.cs b/websocket-sharp/Server/WebSocketServer.cs
index 9401394f..33dbfe97 100644
--- a/websocket-sharp/Server/WebSocketServer.cs
+++ b/websocket-sharp/Server/WebSocketServer.cs
@@ -88,7 +88,7 @@ namespace WebSocketSharp.Server {
         throw new ArgumentException(msg, "url");
       }
 
-      init();
+      _svcHosts = new ServiceHostManager();
     }
 
     /// <summary>
@@ -137,7 +137,7 @@ namespace WebSocketSharp.Server {
     public WebSocketServer(System.Net.IPAddress address, int port, bool secure)
       : base(address, port, "/", secure)
     {
-      init();
+      _svcHosts = new ServiceHostManager();
     }
 
     #endregion
@@ -155,6 +155,7 @@ namespace WebSocketSharp.Server {
         var url = BaseUri.IsAbsoluteUri
                 ? BaseUri.ToString().TrimEnd('/')
                 : String.Empty;
+
         foreach (var path in _svcHosts.Paths)
           yield return url + path;
       }
@@ -180,15 +181,6 @@ namespace WebSocketSharp.Server {
 
     #endregion
 
-    #region Private Methods
-
-    private void init()
-    {
-      _svcHosts = new ServiceHostManager();
-    }
-
-    #endregion
-
     #region Protected Methods
 
     /// <summary>
@@ -199,18 +191,18 @@ namespace WebSocketSharp.Server {
     /// </param>
     protected override void AcceptWebSocket(TcpListenerWebSocketContext context)
     {
-      var websocket = context.WebSocket;
-      var path      = context.Path.UrlDecode();
+      var ws = context.WebSocket;
+      var path = context.Path.UrlDecode();
 
       IServiceHost svcHost;
       if (!_svcHosts.TryGetServiceHost(path, out svcHost))
       {
-        websocket.Close(HttpStatusCode.NotImplemented);
+        ws.Close(HttpStatusCode.NotImplemented);
         return;
       }
 
       if (BaseUri.IsAbsoluteUri)
-        websocket.Url = new Uri(BaseUri, path);
+        ws.Url = new Uri(BaseUri, path);
 
       svcHost.BindWebSocket(context);
     }
@@ -242,6 +234,7 @@ namespace WebSocketSharp.Server {
       svcHost.Uri = BaseUri.IsAbsoluteUri
                   ? new Uri(BaseUri, absPath)
                   : absPath.ToUri();
+
       if (!Sweeping)
         svcHost.Sweeping = false;
 
diff --git a/websocket-sharp/Server/WebSocketServerBase.cs b/websocket-sharp/Server/WebSocketServerBase.cs
index 0b930cf3..7c488e68 100644
--- a/websocket-sharp/Server/WebSocketServerBase.cs
+++ b/websocket-sharp/Server/WebSocketServerBase.cs
@@ -45,11 +45,12 @@ namespace WebSocketSharp.Server {
 
     #region Private Fields
 
-    private Thread      _receiveRequestThread;
     private IPAddress   _address;
-    private bool        _isSecure;
-    private bool        _isSelfHost;
+    private bool        _listening;
     private int         _port;
+    private Thread      _receiveRequestThread;
+    private bool        _secure;
+    private bool        _selfHost;
     private TcpListener _tcpListener;
     private Uri         _uri;
 
@@ -62,7 +63,7 @@ namespace WebSocketSharp.Server {
     /// </summary>
     protected WebSocketServerBase()
     {
-      _isSelfHost = false;
+      _selfHost = false;
     }
 
     /// <summary>
@@ -133,7 +134,7 @@ namespace WebSocketSharp.Server {
       if (!absPath.IsValidAbsolutePath(out msg))
         throw new ArgumentException(msg, "absPath");
 
-      if ((port == 80  && secure) ||
+      if ((port == 80 && secure) ||
           (port == 443 && !secure))
       {
         msg = String.Format(
@@ -141,12 +142,10 @@ namespace WebSocketSharp.Server {
         throw new ArgumentException(msg);
       }
 
-      _address  = address;
-      _port     = port > 0
-                ? port
-                : secure ? 443 : 80;
-      _uri      = absPath.ToUri();
-      _isSecure = secure;
+      _address = address;
+      _port = port > 0 ? port : secure ? 443 : 80;
+      _uri = absPath.ToUri();
+      _secure = secure;
 
       init();
     }
@@ -161,8 +160,7 @@ namespace WebSocketSharp.Server {
     /// <value>
     /// A <see cref="Uri"/> that contains a WebSocket URL.
     /// </value>
-    protected Uri BaseUri
-    {
+    protected Uri BaseUri {
       get {
         return _uri;
       }
@@ -188,6 +186,18 @@ namespace WebSocketSharp.Server {
       }
     }
 
+    /// <summary>
+    /// Gets a value indicating whether the server has been started.
+    /// </summary>
+    /// <value>
+    /// <c>true</c> if the server has been started; otherwise, <c>false</c>.
+    /// </value>
+    public bool IsListening {
+      get {
+        return _listening;
+      }
+    }
+
     /// <summary>
     /// Gets a value indicating whether the server provides secure connection.
     /// </summary>
@@ -196,7 +206,7 @@ namespace WebSocketSharp.Server {
     /// </value>
     public bool IsSecure {
       get {
-        return _isSecure;
+        return _secure;
       }
     }
 
@@ -208,7 +218,7 @@ namespace WebSocketSharp.Server {
     /// </value>
     public bool IsSelfHost {
       get {
-        return _isSelfHost;
+        return _selfHost;
       }
     }
 
@@ -237,43 +247,24 @@ namespace WebSocketSharp.Server {
 
     #region Private Methods
 
-    private void acceptWebSocketAsync(TcpListenerWebSocketContext context)
-    {
-      WaitCallback callback = (state) =>
-      {
-        try
-        {
-          AcceptWebSocket(context);
-        }
-        catch (Exception ex)
-        {
-          onError(ex.Message);
-        }
-      };
-
-      ThreadPool.QueueUserWorkItem(callback);
-    }
-
     private void init()
     {
+      _listening = false;
+      _selfHost = true;
       _tcpListener = new TcpListener(_address, _port);
-      _isSelfHost  = true;
     }
 
     private void init(Uri uri)
     {
       var scheme = uri.Scheme;
-      var host   = uri.DnsSafeHost;
-      var port   = uri.Port;
-      var addrs  = Dns.GetHostAddresses(host);
-
-      _uri      = uri;
-      _address  = addrs[0];
-      _isSecure = scheme == "wss" ? true : false;
-      _port     = port > 0
-                  ? port
-                  : _isSecure ? 443 : 80;
-
+      var host = uri.DnsSafeHost;
+      var port = uri.Port;
+      var addrs = Dns.GetHostAddresses(host);
+
+      _uri = uri;
+      _address = addrs[0];
+      _secure = scheme == "wss" ? true : false;
+      _port = port > 0 ? port : _secure ? 443 : 80;
       init();
     }
 
@@ -281,20 +272,37 @@ namespace WebSocketSharp.Server {
     {
       #if DEBUG
       var callerFrame = new StackFrame(1);
-      var caller      = callerFrame.GetMethod();
+      var caller = callerFrame.GetMethod();
       Console.WriteLine("WSSV: Error@{0}: {1}", caller.Name, message);
       #endif
       OnError.Emit(this, new ErrorEventArgs(message));
     }
 
+    private void processRequestAsync(TcpListenerWebSocketContext context)
+    {
+      WaitCallback callback = (state) =>
+      {
+        try
+        {
+          AcceptWebSocket(context);
+        }
+        catch (Exception ex)
+        {
+          onError(ex.Message);
+        }
+      };
+
+      ThreadPool.QueueUserWorkItem(callback);
+    }
+
     private void receiveRequest()
     {
       while (true)
       {
         try
         {
-          var context = _tcpListener.AcceptWebSocket(_isSecure);
-          acceptWebSocketAsync(context);
+          var context = _tcpListener.AcceptWebSocket(_secure);
+          processRequestAsync(context);
         }
         catch (SocketException)
         {
@@ -323,8 +331,9 @@ namespace WebSocketSharp.Server {
 
       if (!result.Query.IsNullOrEmpty())
       {
-        result  = null;
+        result = null;
         message = "Must not contain the query component: " + uriString;
+
         return false;
       }
 
@@ -363,11 +372,12 @@ namespace WebSocketSharp.Server {
     /// </summary>
     public virtual void Start()
     {
-      if (!_isSelfHost)
+      if (!_selfHost || _listening)
         return;
 
       _tcpListener.Start();
       startReceiveRequestThread();
+      _listening = true;
     }
 
     /// <summary>
@@ -375,11 +385,12 @@ namespace WebSocketSharp.Server {
     /// </summary>
     public virtual void Stop()
     {
-      if (!_isSelfHost)
+      if (!_selfHost || !_listening)
         return;
 
       _tcpListener.Stop();
       _receiveRequestThread.Join(5 * 1000);
+      _listening = false;
     }
 
     #endregion
diff --git a/websocket-sharp/Server/WebSocketServiceHost.cs b/websocket-sharp/Server/WebSocketServiceHost.cs
index acf8638d..3d01f2c5 100644
--- a/websocket-sharp/Server/WebSocketServiceHost.cs
+++ b/websocket-sharp/Server/WebSocketServiceHost.cs
@@ -58,7 +58,7 @@ namespace WebSocketSharp.Server {
 
     internal WebSocketServiceHost()
     {
-      init();
+      _sessions = new WebSocketServiceManager();
     }
 
     #endregion
@@ -87,7 +87,7 @@ namespace WebSocketSharp.Server {
     public WebSocketServiceHost(string url)
       : base(url)
     {
-      init();
+      _sessions = new WebSocketServiceManager();
     }
 
     /// <summary>
@@ -175,7 +175,7 @@ namespace WebSocketSharp.Server {
     public WebSocketServiceHost(System.Net.IPAddress address, int port, string absPath, bool secure)
       : base(address, port, absPath, secure)
     {
-      init();
+      _sessions = new WebSocketServiceManager();
     }
 
     #endregion
@@ -218,15 +218,6 @@ namespace WebSocketSharp.Server {
 
     #endregion
 
-    #region Private Methods
-
-    private void init()
-    {
-      _sessions = new WebSocketServiceManager();
-    }
-
-    #endregion
-
     #region Protected Methods
 
     /// <summary>
@@ -237,16 +228,16 @@ namespace WebSocketSharp.Server {
     /// </param>
     protected override void AcceptWebSocket(TcpListenerWebSocketContext context)
     {
-      var websocket = context.WebSocket;
+      var ws = context.WebSocket;
       var path = context.Path.UrlDecode();
       if (path != Uri.GetAbsolutePath().UrlDecode())
       {
-        websocket.Close(HttpStatusCode.NotImplemented);
+        ws.Close(HttpStatusCode.NotImplemented);
         return;
       }
 
       if (Uri.IsAbsoluteUri)
-        websocket.Url = Uri;
+        ws.Url = Uri;
 
       ((IServiceHost)this).BindWebSocket(context);
     }