diff --git a/websocket-sharp/WebSocket.cs b/websocket-sharp/WebSocket.cs
index 8289a8ef..d71b01a4 100644
--- a/websocket-sharp/WebSocket.cs
+++ b/websocket-sharp/WebSocket.cs
@@ -338,7 +338,7 @@ namespace WebSocketSharp
     ///   </para>
     /// </value>
     /// <exception cref="InvalidOperationException">
-    /// The set operation cannot be used by servers.
+    /// The set operation is not available if this instance is not a client.
     /// </exception>
     public CompressionMethod Compression {
       get {