diff --git a/source/birchwood/client/client.d b/source/birchwood/client/client.d
index 01e53d1..f8c0d82 100644
--- a/source/birchwood/client/client.d
+++ b/source/birchwood/client/client.d
@@ -427,14 +427,24 @@ public class Client : Thread
      *
      * Params:
      *   channel = the channel to leave
+     * Throws:
+     *   `BirchwoodException` if the channel name
+     * is invalid
      */
     public void leaveChannel(string channel)
     {
-        // TODO: Add check for valid and non-empty channel names
-
-        /* Leave the channel */
-        Message leaveMessage = new Message("", "PART", channel);
-        sendMessage(leaveMessage);
+        /* Ensure the channel name contains only valid characters */
+        if(isValidText(channel))
+        {
+            /* Leave the channel */
+            Message leaveMessage = new Message("", "PART", channel);
+            sendMessage(leaveMessage);
+        }
+        /* If invalid characters were present */
+        else
+        {
+            throw new BirchwoodException(ErrorType.ILLEGAL_CHARACTERS);
+        }
     }
 
     /** 
@@ -645,13 +655,11 @@ public class Client : Thread
             }
             else
             {
-                //TODO: Invalid channel name
                 throw new BirchwoodException(ErrorType.INVALID_CHANNEL_NAME);
             }
         }
         else
         {
-            //TODO: Illegal characters
             throw new BirchwoodException(ErrorType.ILLEGAL_CHARACTERS);
         }
     }