diff --git a/irc/client.go b/irc/client.go
index f96d6ff0..e5c04463 100644
--- a/irc/client.go
+++ b/irc/client.go
@@ -165,6 +165,10 @@ func (client *Client) IdleTime() time.Duration {
 	return time.Since(client.atime)
 }
 
+func (client *Client) IdleSeconds() uint64 {
+	return uint64(client.IdleTime().Seconds())
+}
+
 func (client *Client) HasNick() bool {
 	return client.nick != ""
 }
diff --git a/irc/reply.go b/irc/reply.go
index 640106e4..1ce42521 100644
--- a/irc/reply.go
+++ b/irc/reply.go
@@ -246,11 +246,39 @@ func RplYoureOper(server *Server) Reply {
 	return NewNumericReply(server, RPL_YOUREOPER, ":You are now an IRC operator")
 }
 
-func RplWhoisUser(server *Server, client *Client) Reply {
-	return NewNumericReply(server, RPL_WHOISUSER, "%s %s %s * :%s",
+func RplWhoisUser(client *Client) Reply {
+	return NewNumericReply(client.server, RPL_WHOISUSER, "%s %s %s * :%s",
 		client.Nick(), client.username, client.hostname, client.realname)
 }
 
+func RplWhoisOperator(client *Client) Reply {
+	return NewNumericReply(client.server, RPL_WHOISOPERATOR,
+		"%s :is an IRC operator", client.Nick())
+}
+
+func RplWhoisIdle(client *Client) Reply {
+	return NewNumericReply(client.server, RPL_WHOISIDLE,
+		"%s %d :seconds idle", client.Nick(), client.IdleSeconds())
+}
+
+// TODO check message length
+func RplWhoisChannels(client *Client) Reply {
+	chstrs := make([]string, len(client.channels))
+	index := 0
+	for channel := range client.channels {
+		if channel.members[client][ChannelOperator] {
+			chstrs[index] = "@" + channel.name
+		} else if channel.members[client][Voice] {
+			chstrs[index] = "+" + channel.name
+		} else {
+			chstrs[index] = channel.name
+		}
+		index += 1
+	}
+	return NewNumericReply(client.server, RPL_WHOISCHANNELS,
+		"%s :%s", client.Nick(), strings.Join(chstrs, " "))
+}
+
 func RplEndOfWhois(server *Server) Reply {
 	return NewNumericReply(server, RPL_ENDOFWHOIS, ":End of WHOIS list")
 }
diff --git a/irc/server.go b/irc/server.go
index 790d899c..b5199ce2 100644
--- a/irc/server.go
+++ b/irc/server.go
@@ -451,12 +451,19 @@ func (m *WhoisCommand) HandleServer(server *Server) {
 
 	for _, mask := range m.masks {
 		// TODO implement wildcard matching
-		mclient := server.clients[mask]
-		if mclient != nil {
-			client.Reply(RplWhoisUser(server, mclient))
+		mclient := server.clients.Get(mask)
+		if mclient == nil {
+			client.Reply(ErrNoSuchNick(server, mask))
+			continue
 		}
+		client.Reply(RplWhoisUser(mclient))
+		if client.flags[Operator] {
+			client.Reply(RplWhoisOperator(mclient))
+		}
+		client.Reply(RplWhoisIdle(mclient))
+		client.Reply(RplWhoisChannels(mclient))
+		client.Reply(RplEndOfWhois(server))
 	}
-	client.Reply(RplEndOfWhois(server))
 }
 
 func (msg *ChannelModeCommand) HandleServer(server *Server) {