diff --git a/rosella.go b/rosella.go
index c99ba25..de7f159 100644
--- a/rosella.go
+++ b/rosella.go
@@ -41,23 +41,27 @@ type ChannelMode struct {
 	secret      bool //Channel is hidden from LIST
 	topicLocked bool //Only ops may change topic
 	moderated   bool //Only ops and voiced may speak
+	noExternal  bool //Only users in the channel may talk to it
 }
 
 func (m *ChannelMode) String() string {
-		modeStr := ""
-		if m.anonymous {
-			modeStr += "a"
-		}
-		if m.secret {
-			modeStr += "s"
-		}
-		if m.topicLocked {
-			modeStr += "t"
-		}
-		if m.moderated {
-			modeStr += "m"
-		}
-		return modeStr
+	modeStr := ""
+	if m.anonymous {
+		modeStr += "a"
+	}
+	if m.secret {
+		modeStr += "s"
+	}
+	if m.topicLocked {
+		modeStr += "t"
+	}
+	if m.moderated {
+		modeStr += "m"
+	}
+	if m.noExternal {
+		modeStr += "n"
+	}
+	return modeStr
 }
 
 type ClientMode struct {
diff --git a/server.go b/server.go
index f5ddd7d..bc36a52 100644
--- a/server.go
+++ b/server.go
@@ -153,6 +153,13 @@ func (s *Server) handleEvent(e Event) {
 		client, clientExists := s.clientMap[strings.ToLower(args[0])]
 
 		if chanExists {
+			if channel.mode.noExternal {
+				if _, inChannel := channel.clientMap[strings.ToLower(e.client.nick)]; !inChannel {
+					//Not in channel, not allowed to send
+					e.client.reply(errCannotSend, args[0])
+					return
+				}
+			}
 			if channel.mode.moderated {
 				clientMode := channel.modeMap[strings.ToLower(e.client.nick)]
 				if !clientMode.operator && !clientMode.voice {
@@ -164,6 +171,8 @@ func (s *Server) handleEvent(e Event) {
 			for _, c := range channel.clientMap {
 				if c != e.client {
 					c.reply(rplMsg, e.client.nick, args[0], message)
+					e.client.reply(errCannotSend, args[0])
+					return
 				}
 			}
 		} else if clientExists {