diff --git a/websocket-sharp/Server/WebSocketServer.cs b/websocket-sharp/Server/WebSocketServer.cs
index 9125a8a0..483a293a 100644
--- a/websocket-sharp/Server/WebSocketServer.cs
+++ b/websocket-sharp/Server/WebSocketServer.cs
@@ -1088,6 +1088,10 @@ namespace WebSocketSharp.Server
     /// <summary>
     /// Starts receiving the WebSocket handshake requests.
     /// </summary>
+    /// <remarks>
+    /// This method does nothing if the server has already started or
+    /// it is shutting down.
+    /// </remarks>
     public void Start ()
     {
       var sslConfig = getSslConfiguration ();