diff --git a/build.sh b/build.sh
index 725dde50..f6bb868f 100755
--- a/build.sh
+++ b/build.sh
@@ -1,4 +1,4 @@
 #!/bin/bash
 export GOPATH="$PWD"
 go get "code.google.com/p/go.crypto/bcrypt"
-go install -v ergonomadic genpasswd
+go install ergonomadic genpasswd
diff --git a/src/irc/channel.go b/src/irc/channel.go
index cb691b6d..c33f112a 100644
--- a/src/irc/channel.go
+++ b/src/irc/channel.go
@@ -1,9 +1,13 @@
 package irc
 
+import (
+	"log"
+)
+
 type Channel struct {
 	server    *Server
-	replies   chan<- Reply
 	commands  chan<- ChannelCommand
+	replies   chan<- Reply
 	name      string
 	key       string
 	topic     string
@@ -27,28 +31,6 @@ type ChannelCommand interface {
 	HandleChannel(channel *Channel)
 }
 
-type JoinChannelCommand struct {
-	*JoinCommand
-	key string
-}
-
-type PartChannelCommand struct {
-	Command
-	message string
-}
-
-type GetTopicChannelCommand struct {
-	*TopicCommand
-}
-
-type SetTopicChannelCommand struct {
-	*TopicCommand
-}
-
-type PrivMsgChannelCommand struct {
-	*PrivMsgCommand
-}
-
 // NewChannel creates a new channel from a `Server` and a `name` string, which
 // must be unique on the server.
 func NewChannel(s *Server, name string) *Channel {
@@ -69,14 +51,17 @@ func NewChannel(s *Server, name string) *Channel {
 // Forward `Reply`s to all `User`s of the `Channel`.
 func (ch *Channel) receiveReplies(replies <-chan Reply) {
 	for reply := range replies {
-		for client := range ch.members {
-			client.replies <- reply
+		for user := range ch.members {
+			if user != reply.Source() {
+				user.replies <- reply
+			}
 		}
 	}
 }
 
 func (ch *Channel) receiveCommands(commands <-chan ChannelCommand) {
 	for command := range commands {
+		log.Printf("%s %T %+v", ch.Id(), command, command)
 		command.HandleChannel(ch)
 	}
 }
@@ -95,29 +80,46 @@ func (ch *Channel) IsEmpty() bool {
 	return len(ch.members) == 0
 }
 
+func (channel *Channel) GetTopic(replier Replier) {
+	if channel.topic == "" {
+		replier.Replies() <- RplNoTopic(channel)
+		return
+	}
+
+	replier.Replies() <- RplTopic(channel)
+}
+
+func (channel *Channel) Id() string {
+	return channel.name
+}
+
+func (channel *Channel) PublicId() string {
+	return channel.name
+}
+
 //
 // commands
 //
 
-func (m *JoinChannelCommand) HandleChannel(channel *Channel) {
+func (m *JoinCommand) HandleChannel(channel *Channel) {
 	client := m.Client()
 	user := client.user
 
-	if channel.key != m.key {
+	if channel.key != m.channels[channel.name] {
 		client.user.replies <- ErrBadChannelKey(channel)
 		return
 	}
 
-	channel.members.Add(client.user)
-	client.user.channels.Add(channel)
+	channel.members.Add(user)
+	user.channels.Add(channel)
 
 	channel.replies <- RplJoin(channel, user)
 	channel.GetTopic(user)
-	client.user.replies <- RplNamReply(channel)
-	client.user.replies <- RplEndOfNames(channel.server)
+	user.replies <- RplNamReply(channel)
+	user.replies <- RplEndOfNames(channel.server)
 }
 
-func (m *PartChannelCommand) HandleChannel(channel *Channel) {
+func (m *PartCommand) HandleChannel(channel *Channel) {
 	user := m.Client().user
 
 	if !channel.members[user] {
@@ -140,25 +142,7 @@ func (m *PartChannelCommand) HandleChannel(channel *Channel) {
 	}
 }
 
-func (channel *Channel) GetTopic(user *User) {
-	if !channel.members[user] {
-		user.replies <- ErrNotOnChannel(channel)
-		return
-	}
-
-	if channel.topic == "" {
-		user.replies <- RplNoTopic(channel)
-		return
-	}
-
-	user.replies <- RplTopic(channel)
-}
-
-func (m *GetTopicChannelCommand) HandleChannel(channel *Channel) {
-	channel.GetTopic(m.Client().user)
-}
-
-func (m *SetTopicChannelCommand) HandleChannel(channel *Channel) {
+func (m *TopicCommand) HandleChannel(channel *Channel) {
 	user := m.Client().user
 
 	if !channel.members[user] {
@@ -166,6 +150,11 @@ func (m *SetTopicChannelCommand) HandleChannel(channel *Channel) {
 		return
 	}
 
+	if m.topic == "" {
+		channel.GetTopic(user)
+		return
+	}
+
 	channel.topic = m.topic
 
 	if channel.topic == "" {
@@ -176,6 +165,6 @@ func (m *SetTopicChannelCommand) HandleChannel(channel *Channel) {
 	channel.replies <- RplTopic(channel)
 }
 
-func (m *PrivMsgChannelCommand) HandleChannel(channel *Channel) {
+func (m *PrivMsgCommand) HandleChannel(channel *Channel) {
 	channel.replies <- RplPrivMsgChannel(channel, m.Client().user, m.message)
 }
diff --git a/src/irc/client.go b/src/irc/client.go
index 37ee72cb..bcaa34b9 100644
--- a/src/irc/client.go
+++ b/src/irc/client.go
@@ -7,9 +7,13 @@ import (
 	"time"
 )
 
+type Replier interface {
+	Identifier
+	Replies() chan<- Reply
+}
+
 type Client struct {
 	conn       net.Conn
-	replies    chan<- Reply
 	username   string
 	realname   string
 	hostname   string
@@ -20,6 +24,12 @@ type Client struct {
 	server     *Server
 	atime      time.Time
 	user       *User
+	replies    chan<- Reply
+}
+
+type ClientMessage interface {
+	Client() *Client
+	SetClient(*Client)
 }
 
 type ClientSet map[*Client]bool
@@ -36,10 +46,7 @@ func NewClient(server *Server, conn net.Conn) *Client {
 		replies:  replies,
 	}
 
-	// Connect the conn to the server.
 	go client.readConn(read)
-
-	// Connect the reply channel to the conn.
 	go client.writeConn(write, replies)
 
 	return client
@@ -51,7 +58,7 @@ func (c *Client) readConn(recv <-chan string) {
 
 		m, err := ParseCommand(str)
 		if err != nil {
-			// TODO handle error
+			c.replies <- ErrNeedMoreParams(c.server, str)
 			continue
 		}
 
@@ -68,6 +75,14 @@ func (c *Client) writeConn(write chan<- string, replies <-chan Reply) {
 	}
 }
 
+func (c *Client) Replies() chan<- Reply {
+	return c.replies
+}
+
+func (c *Client) Server() *Server {
+	return c.server
+}
+
 func (c *Client) Nick() string {
 	if c.user != nil {
 		return c.user.nick
diff --git a/src/irc/commands.go b/src/irc/commands.go
index 164ff34f..8fbf1b1f 100644
--- a/src/irc/commands.go
+++ b/src/irc/commands.go
@@ -6,12 +6,6 @@ import (
 	"strings"
 )
 
-type Command interface {
-	Client() *Client
-	SetClient(*Client)
-	Handle(*Server)
-}
-
 var (
 	NotEnoughArgsError = errors.New("not enough arguments")
 )
@@ -28,7 +22,59 @@ func (base *BaseCommand) SetClient(c *Client) {
 	base.client = c
 }
 
-// unknown <command> [args...]
+var (
+	ErrParseCommand   = errors.New("failed to parse message")
+	parseCommandFuncs = map[string]func([]string) (Command, error){
+		"JOIN":    NewJoinCommand,
+		"MODE":    NewModeCommand,
+		"NICK":    NewNickCommand,
+		"PART":    NewPartCommand,
+		"PASS":    NewPassCommand,
+		"PING":    NewPingCommand,
+		"PONG":    NewPongCommand,
+		"PRIVMSG": NewPrivMsgCommand,
+		"QUIT":    NewQuitCommand,
+		"TOPIC":   NewTopicCommand,
+		"USER":    NewUserMsgCommand,
+	}
+)
+
+func ParseCommand(line string) (Command, error) {
+	command, args := parseLine(line)
+	constructor := parseCommandFuncs[command]
+	if constructor == nil {
+		return NewUnknownCommand(command, args), nil
+	}
+	return constructor(args)
+}
+
+func parseArg(line string) (arg string, rest string) {
+	if line == "" {
+		return
+	}
+
+	if strings.HasPrefix(line, ":") {
+		arg = line[1:]
+	} else {
+		parts := strings.SplitN(line, " ", 2)
+		arg = parts[0]
+		if len(parts) > 1 {
+			rest = parts[1]
+		}
+	}
+	return
+}
+
+func parseLine(line string) (command string, args []string) {
+	args = make([]string, 0)
+	for arg, rest := parseArg(line); arg != ""; arg, rest = parseArg(rest) {
+		args = append(args, arg)
+	}
+	command, args = strings.ToUpper(args[0]), args[1:]
+	return
+}
+
+// <command> [args...]
 
 type UnknownCommand struct {
 	*BaseCommand
@@ -36,7 +82,7 @@ type UnknownCommand struct {
 	args    []string
 }
 
-func NewUnknownCommand(command string, args []string) Command {
+func NewUnknownCommand(command string, args []string) *UnknownCommand {
 	return &UnknownCommand{
 		BaseCommand: &BaseCommand{},
 		command:     command,
@@ -44,10 +90,6 @@ func NewUnknownCommand(command string, args []string) Command {
 	}
 }
 
-func (m *UnknownCommand) Handle(s *Server) {
-	m.Client().replies <- ErrUnknownCommand(s, m.command)
-}
-
 // PING <server1> [ <server2> ]
 
 type PingCommand struct {
@@ -128,7 +170,7 @@ func NewNickCommand(args []string) (Command, error) {
 
 // USER <user> <mode> <unused> <realname>
 
-type UserCommand struct {
+type UserMsgCommand struct {
 	*BaseCommand
 	user     string
 	mode     uint8
@@ -136,11 +178,11 @@ type UserCommand struct {
 	realname string
 }
 
-func NewUserCommand(args []string) (Command, error) {
+func NewUserMsgCommand(args []string) (Command, error) {
 	if len(args) != 4 {
 		return nil, NotEnoughArgsError
 	}
-	msg := &UserCommand{
+	msg := &UserMsgCommand{
 		BaseCommand: &BaseCommand{},
 		user:        args[0],
 		unused:      args[2],
@@ -174,26 +216,36 @@ func NewQuitCommand(args []string) (Command, error) {
 
 type JoinCommand struct {
 	*BaseCommand
-	channels []string
-	keys     []string
+	channels map[string]string
 	zero     bool
 }
 
 func NewJoinCommand(args []string) (Command, error) {
 	msg := &JoinCommand{
 		BaseCommand: &BaseCommand{},
+		channels:    make(map[string]string),
 	}
-	if len(args) > 0 {
-		if args[0] == "0" {
-			msg.zero = true
-		} else {
-			msg.channels = strings.Split(args[0], ",")
-		}
 
-		if len(args) > 1 {
-			msg.keys = strings.Split(args[1], ",")
+	if len(args) == 0 {
+		return nil, NotEnoughArgsError
+	}
+
+	if args[0] == "0" {
+		msg.zero = true
+		return msg, nil
+	}
+
+	channels := strings.Split(args[0], ",")
+	keys := make([]string, len(channels))
+	if len(args) > 1 {
+		for i, key := range strings.Split(args[1], ",") {
+			keys[i] = key
 		}
 	}
+	for i, channel := range channels {
+		msg.channels[channel] = keys[i]
+	}
+
 	return msg, nil
 }
 
@@ -268,40 +320,25 @@ func NewTopicCommand(args []string) (Command, error) {
 	return msg, nil
 }
 
-// LOGIN <nick> <password>
-
-type LoginCommand struct {
+type ModeCommand struct {
 	*BaseCommand
-	nick     string
-	password string
+	nickname string
+	modes    string
 }
 
-func NewLoginCommand(args []string) (Command, error) {
-	if len(args) < 2 {
+func NewModeCommand(args []string) (Command, error) {
+	if len(args) == 0 {
 		return nil, NotEnoughArgsError
 	}
-	return &LoginCommand{
+
+	cmd := &ModeCommand{
 		BaseCommand: &BaseCommand{},
-		nick:        args[0],
-		password:    args[1],
-	}, nil
-}
-
-// RESERVE <nick> <password>
-
-type ReserveCommand struct {
-	*BaseCommand
-	nick     string
-	password string
-}
-
-func NewReserveCommand(args []string) (Command, error) {
-	if len(args) < 2 {
-		return nil, NotEnoughArgsError
+		nickname:    args[0],
 	}
-	return &ReserveCommand{
-		BaseCommand: &BaseCommand{},
-		nick:        args[0],
-		password:    args[1],
-	}, nil
+
+	if len(args) > 1 {
+		cmd.modes = args[1]
+	}
+
+	return cmd, nil
 }
diff --git a/src/irc/nickserv.go b/src/irc/nickserv.go
new file mode 100644
index 00000000..ce5d44b7
--- /dev/null
+++ b/src/irc/nickserv.go
@@ -0,0 +1,135 @@
+package irc
+
+import (
+	"log"
+)
+
+type NickServCommand interface {
+	ClientMessage
+	HandleNickServ(*NickServ)
+}
+
+type NickServ struct {
+	*Service
+}
+
+func NewNickServ(s *Server) *NickServ {
+	ns := &NickServ{}
+	ns.Service = NewService(s, "NickServ", func(m *PrivMsgCommand) {
+		m.HandleNickServ(ns)
+	})
+	return ns
+}
+
+var (
+	parseNickServCommandFuncs = map[string]func([]string) (NickServCommand, error){
+		"REGISTER": NewRegisterCommand,
+		"IDENTIFY": NewIdentifyCommand,
+	}
+)
+
+//
+// commands
+//
+
+func (m *PrivMsgCommand) HandleNickServ(ns *NickServ) {
+	command, args := parseLine(m.message)
+	constructor := parseNickServCommandFuncs[command]
+	if constructor == nil {
+		ns.Reply(m.Client(), "Unknown command.")
+		return
+	}
+
+	cmd, err := constructor(args)
+	if err != nil {
+		ns.Reply(m.Client(), "Not enough parameters.")
+		return
+	}
+
+	cmd.SetClient(m.Client())
+	log.Printf("%s %T %+v", ns.Id(), cmd, cmd)
+	cmd.HandleNickServ(ns)
+}
+
+//
+// sub-commands
+//
+
+type RegisterCommand struct {
+	*BaseCommand
+	password string
+	email    string
+}
+
+func NewRegisterCommand(args []string) (NickServCommand, error) {
+	if len(args) == 0 {
+		return nil, NotEnoughArgsError
+	}
+
+	cmd := &RegisterCommand{
+		BaseCommand: &BaseCommand{},
+		password:    args[0],
+	}
+	if len(args) > 1 {
+		cmd.email = args[1]
+	}
+	return cmd, nil
+}
+
+func (m *RegisterCommand) HandleNickServ(ns *NickServ) {
+	client := m.Client()
+
+	if client.user != nil {
+		ns.Reply(client, "You are already registered.")
+		return
+	}
+
+	if ns.server.users[client.nick] != nil {
+		ns.Reply(client, "That nick is already registered.")
+		return
+	}
+
+	user := NewUser(client.nick, m.password, ns.server)
+	ns.server.users[client.nick] = user
+	ns.Reply(client, "You have registered.")
+
+	if !user.Login(client, client.nick, m.password) {
+		ns.Reply(client, "Login failed.")
+	}
+	ns.Reply(client, "Logged in.")
+}
+
+type IdentifyCommand struct {
+	*BaseCommand
+	password string
+}
+
+func NewIdentifyCommand(args []string) (NickServCommand, error) {
+	if len(args) == 0 {
+		return nil, NotEnoughArgsError
+	}
+
+	return &IdentifyCommand{
+		BaseCommand: &BaseCommand{},
+		password:    args[0],
+	}, nil
+}
+
+func (m *IdentifyCommand) HandleNickServ(ns *NickServ) {
+	client := m.Client()
+	if client.user != nil {
+		ns.Reply(client, "That nick is already registered.")
+		return
+	}
+
+	user := ns.server.users[client.nick]
+	if user == nil {
+		ns.Reply(client, "No such nick.")
+		return
+	}
+
+	if !user.Login(client, client.nick, m.password) {
+		ns.Reply(client, "Login failed.")
+	}
+	ns.Reply(client, "Logged in.")
+}
diff --git a/src/irc/parse.go b/src/irc/parse.go
deleted file mode 100644
index b3f8f365..00000000
--- a/src/irc/parse.go
+++ /dev/null
@@ -1,60 +0,0 @@
-package irc
-
-import (
-	"errors"
-	"strings"
-)
-
-type ParseFunc func([]string) (Command, error)
-
-var (
-	ErrParseCommand   = errors.New("failed to parse message")
-	parseCommandFuncs = map[string]ParseFunc{
-		"JOIN":    NewJoinCommand,
-		"LOGIN":   NewLoginCommand,
-		"NICK":    NewNickCommand,
-		"PART":    NewPartCommand,
-		"PASS":    NewPassCommand,
-		"PING":    NewPingCommand,
-		"PONG":    NewPongCommand,
-		"PRIVMSG": NewPrivMsgCommand,
-		"QUIT":    NewQuitCommand,
-		"TOPIC":   NewTopicCommand,
-		"USER":    NewUserCommand,
-	}
-)
-
-func ParseCommand(line string) (Command, error) {
-	command, args := parseLine(line)
-	constructor := parseCommandFuncs[command]
-	if constructor == nil {
-		return NewUnknownCommand(command, args), nil
-	}
-	return constructor(args)
-}
-
-func parseArg(line string) (arg string, rest string) {
-	if line == "" {
-		return
-	}
-
-	if strings.HasPrefix(line, ":") {
-		arg = line[1:]
-	} else {
-		parts := strings.SplitN(line, " ", 2)
-		arg = parts[0]
-		if len(parts) > 1 {
-			rest = parts[1]
-		}
-	}
-	return
-}
-
-func parseLine(line string) (command string, args []string) {
-	args = make([]string, 0)
-	for arg, rest := parseArg(line); arg != ""; arg, rest = parseArg(rest) {
-		args = append(args, arg)
-	}
-	command, args = args[0], args[1:]
-	return
-}
diff --git a/src/irc/reply.go b/src/irc/reply.go
index 5a2e9f4e..14c05666 100644
--- a/src/irc/reply.go
+++ b/src/irc/reply.go
@@ -9,10 +9,12 @@ import (
 type Identifier interface {
 	Id() string
 	PublicId() string
+	Nick() string
 }
 
 type Reply interface {
 	String(client *Client) string
+	Source() Identifier
 }
 
 type BasicReply struct {
@@ -21,7 +23,8 @@ type BasicReply struct {
 	message string
 }
 
-func NewBasicReply(source Identifier, code string, format string, args ...interface{}) *BasicReply {
+func NewBasicReply(source Identifier, code string,
+	format string, args ...interface{}) *BasicReply {
 	message := fmt.Sprintf(format, args...)
 	fullMessage := fmt.Sprintf(":%s %s %s\r\n", source.Id(), code, message)
 	return &BasicReply{source, code, fullMessage}
@@ -31,11 +34,16 @@ func (reply *BasicReply) String(client *Client) string {
 	return reply.message
 }
 
+func (reply *BasicReply) Source() Identifier {
+	return reply.source
+}
+
 type NumericReply struct {
 	*BasicReply
 }
 
-func NewNumericReply(source Identifier, code string, format string, args ...interface{}) *NumericReply {
+func NewNumericReply(source Identifier, code string,
+	format string, args ...interface{}) *NumericReply {
 	return &NumericReply{&BasicReply{source, code, fmt.Sprintf(format, args...)}}
 }
 
@@ -47,7 +55,7 @@ func (reply *NumericReply) String(client *Client) string {
 // messaging replies
 
 func RplPrivMsg(source Identifier, target Identifier, message string) Reply {
-	return NewBasicReply(source, RPL_PRIVMSG, "%s :%s", target, message)
+	return NewBasicReply(source, RPL_PRIVMSG, "%s :%s", target.Nick(), message)
 }
 
 func RplNick(client *Client, newNick string) Reply {
diff --git a/src/irc/server.go b/src/irc/server.go
index adb44a4b..ba7a51e5 100644
--- a/src/irc/server.go
+++ b/src/irc/server.go
@@ -10,15 +10,22 @@ import (
 type ClientNameMap map[string]*Client
 type ChannelNameMap map[string]*Channel
 type UserNameMap map[string]*User
+type ServiceNameMap map[string]*Service
+
+type Command interface {
+	ClientMessage
+	Handle(*Server)
+}
 
 type Server struct {
 	hostname string
 	ctime    time.Time
 	name     string
-	commands chan<- Command
 	password []byte
 	users    UserNameMap
 	channels ChannelNameMap
+	services ServiceNameMap
+	commands chan<- Command
 }
 
 func NewServer(name string) *Server {
@@ -29,13 +36,16 @@ func NewServer(name string) *Server {
 		commands: commands,
 		users:    make(UserNameMap),
 		channels: make(ChannelNameMap),
+		services: make(ServiceNameMap),
 	}
 	go server.receiveCommands(commands)
+	NewNickServ(server)
 	return server
 }
 
 func (server *Server) receiveCommands(commands <-chan Command) {
 	for command := range commands {
+		log.Printf("%s %T %+v", server.Id(), command, command)
 		command.Client().atime = time.Now()
 		command.Handle(server)
 	}
@@ -75,10 +85,10 @@ func (s *Server) GetOrMakeChannel(name string) *Channel {
 // Send a message to clients of channels fromClient is a member.
 func (s *Server) InterestedUsers(fromUser *User) UserSet {
 	users := make(UserSet)
-	users[fromUser] = true
+	users.Add(fromUser)
 	for channel := range fromUser.channels {
 		for user := range channel.members {
-			users[user] = true
+			users.Add(user)
 		}
 	}
 
@@ -97,11 +107,6 @@ func (s *Server) tryRegister(c *Client) {
 	}
 }
 
-func (s *Server) ChangeUserMode(c *Client, modes []string) {
-	// Don't allow any mode changes.
-	c.replies <- RplUModeIs(s, c)
-}
-
 func (s *Server) Id() string {
 	return s.hostname
 }
@@ -110,6 +115,10 @@ func (s *Server) PublicId() string {
 	return s.Id()
 }
 
+func (s *Server) Nick() string {
+	return s.name
+}
+
 func (s *Server) DeleteChannel(channel *Channel) {
 	delete(s.channels, channel.name)
 }
@@ -118,6 +127,10 @@ func (s *Server) DeleteChannel(channel *Channel) {
 // commands
 //
 
+func (m *UnknownCommand) Handle(s *Server) {
+	m.Client().replies <- ErrUnknownCommand(s, m.command)
+}
+
 func (m *PingCommand) Handle(s *Server) {
 	m.Client().replies <- RplPong(s)
 }
@@ -149,7 +162,7 @@ func (m *NickCommand) Handle(s *Server) {
 	c.user.replies <- ErrNoPrivileges(s)
 }
 
-func (m *UserCommand) Handle(s *Server) {
+func (m *UserMsgCommand) Handle(s *Server) {
 	c := m.Client()
 	if c.username != "" {
 		c.replies <- ErrAlreadyRegistered(s)
@@ -162,19 +175,25 @@ func (m *UserCommand) Handle(s *Server) {
 
 func (m *QuitCommand) Handle(s *Server) {
 	c := m.Client()
-	reply := RplQuit(c, m.message)
-	for user := range s.InterestedUsers(c.user) {
-		user.replies <- reply
+
+	user := c.user
+	if user != nil {
+		reply := RplQuit(c, m.message)
+		for user := range s.InterestedUsers(c.user) {
+			user.replies <- reply
+		}
 	}
 	c.conn.Close()
-	user := c.user
-	user.LogoutClient(c)
+	if user == nil {
+		return
+	}
 
+	user.LogoutClient(c)
 	if !user.HasClients() {
-		cmd := &PartChannelCommand{
-			Command: m,
+		cmd := &PartCommand{
+			BaseCommand: &BaseCommand{c},
 		}
-		for channel := range c.user.channels {
+		for channel := range user.channels {
 			channel.commands <- cmd
 		}
 	}
@@ -182,27 +201,39 @@ func (m *QuitCommand) Handle(s *Server) {
 
 func (m *JoinCommand) Handle(s *Server) {
 	c := m.Client()
+
+	if c.user == nil {
+		for name := range m.channels {
+			c.replies <- ErrNoSuchChannel(s, name)
+		}
+		return
+	}
+
 	if m.zero {
-		cmd := &PartChannelCommand{
-			Command: m,
+		cmd := &PartCommand{
+			BaseCommand: &BaseCommand{c},
 		}
 		for channel := range c.user.channels {
 			channel.commands <- cmd
 		}
-	} else {
-		for i, name := range m.channels {
-			key := ""
-			if len(m.keys) > i {
-				key = m.keys[i]
-			}
+		return
+	}
 
-			s.GetOrMakeChannel(name).commands <- &JoinChannelCommand{m, key}
-		}
+	for name := range m.channels {
+		s.GetOrMakeChannel(name).commands <- m
 	}
 }
 
 func (m *PartCommand) Handle(s *Server) {
 	user := m.Client().user
+
+	if user == nil {
+		for _, chname := range m.channels {
+			m.Client().replies <- ErrNoSuchChannel(s, chname)
+		}
+		return
+	}
+
 	for _, chname := range m.channels {
 		channel := s.channels[chname]
 
@@ -211,82 +242,60 @@ func (m *PartCommand) Handle(s *Server) {
 			continue
 		}
 
-		channel.commands <- &PartChannelCommand{m, m.message}
+		channel.commands <- m
 	}
 }
 
 func (m *TopicCommand) Handle(s *Server) {
 	user := m.Client().user
+
+	if user == nil {
+		m.Client().replies <- ErrNoSuchChannel(s, m.channel)
+		return
+	}
+
 	channel := s.channels[m.channel]
 	if channel == nil {
 		user.replies <- ErrNoSuchChannel(s, m.channel)
 		return
 	}
 
-	if m.topic == "" {
-		channel.commands <- &GetTopicChannelCommand{m}
-		return
-	}
-
-	channel.commands <- &SetTopicChannelCommand{m}
+	channel.commands <- m
 }
 
 func (m *PrivMsgCommand) Handle(s *Server) {
+	service := s.services[m.target]
+	if service != nil {
+		service.commands <- m
+		return
+	}
+
 	user := m.Client().user
+	if user == nil {
+		m.Client().replies <- ErrNoSuchNick(s, m.target)
+		return
+	}
 
 	if m.TargetIsChannel() {
 		channel := s.channels[m.target]
 		if channel == nil {
-			user.replies <- ErrNoSuchNick(s, m.target)
+			user.replies <- ErrNoSuchChannel(s, m.target)
 			return
 		}
 
-		channel.commands <- &PrivMsgChannelCommand{m}
+		channel.commands <- m
 		return
 	}
 
 	target := s.users[m.target]
-	if target != nil {
-		target.replies <- ErrNoSuchNick(s, m.target)
+	if target == nil {
+		user.replies <- ErrNoSuchNick(s, m.target)
 		return
 	}
 
-	target.replies <- RplPrivMsg(user, target, m.message)
+	target.commands <- m
 }
 
-func (m *LoginCommand) Handle(s *Server) {
-	client := m.Client()
-	if client.user != nil {
-		client.replies <- ErrAlreadyRegistered(s)
-		return
-	}
-
-	user := s.users[m.nick]
-	if user == nil {
-		client.replies <- ErrNoSuchNick(s, m.nick)
-		return
-	}
-
-	if !user.Login(client, m.nick, m.password) {
-		client.replies <- ErrRestricted(s)
-		return
-	}
-
-	client.replies <- RplNick(client, m.nick)
-	// TODO join channels
-}
-
-func (m *ReserveCommand) Handle(s *Server) {
-	client := m.Client()
-	if client.user != nil {
-		client.replies <- ErrAlreadyRegistered(s)
-		return
-	}
-
-	if s.users[m.nick] != nil {
-		client.replies <- ErrNickNameInUse(s, m.nick)
-		return
-	}
-
-	s.users[m.nick] = NewUser(m.nick, m.password, s)
+func (m *ModeCommand) Handle(s *Server) {
+	m.Client().replies <- RplUModeIs(s, m.Client())
 }
diff --git a/src/irc/service.go b/src/irc/service.go
new file mode 100644
index 00000000..4f3842ce
--- /dev/null
+++ b/src/irc/service.go
@@ -0,0 +1,64 @@
+package irc
+
+import (
+	"fmt"
+	"log"
+)
+
+type ServiceCommand interface {
+	Command
+	HandleService(*Service)
+}
+
+type PrivMsgCommandFunc func(*PrivMsgCommand)
+
+type Service struct {
+	server   *Server
+	name     string
+	commands chan<- ServiceCommand
+	Handle   PrivMsgCommandFunc
+}
+
+func NewService(s *Server, name string, Handle PrivMsgCommandFunc) *Service {
+	commands := make(chan ServiceCommand)
+	service := &Service{
+		server:   s,
+		name:     name,
+		commands: commands,
+		Handle:   Handle,
+	}
+	go service.receiveCommands(commands)
+	s.services[name] = service
+	return service
+}
+
+func (service *Service) receiveCommands(commands <-chan ServiceCommand) {
+	for command := range commands {
+		log.Printf("%s %T %+V", service.Id(), command, command)
+		command.HandleService(service)
+	}
+}
+
+func (service *Service) Id() string {
+	return fmt.Sprintf("%s!%s@%s", service.name, service.name, service.server.name)
+}
+
+func (service *Service) PublicId() string {
+	return service.Id()
+}
+
+func (service *Service) Nick() string {
+	return service.name
+}
+
+func (service *Service) Reply(client *Client, message string) {
+	client.replies <- RplPrivMsg(service, client, message)
+}
+
+//
+// commands
+//
+
+func (m *PrivMsgCommand) HandleService(s *Service) {
+	s.Handle(m)
+}
diff --git a/src/irc/user.go b/src/irc/user.go
index b29f0fbf..1884a151 100644
--- a/src/irc/user.go
+++ b/src/irc/user.go
@@ -3,16 +3,22 @@ package irc
 import (
 	"code.google.com/p/go.crypto/bcrypt"
 	"fmt"
+	"log"
 )
 
+type UserCommand interface {
+	Command
+	HandleUser(*User)
+}
+
 type User struct {
 	nick     string
 	hash     []byte
 	server   *Server
-	replies  chan<- Reply
-	commands <-chan Command
 	clients  ClientSet
 	channels ChannelSet
+	commands chan<- UserCommand
+	replies  chan<- Reply
 }
 
 type UserSet map[*User]bool
@@ -30,21 +36,32 @@ func NewUser(nick string, password string, server *Server) *User {
 	if err != nil {
 		panic("bcrypt failed; cannot generate password hash")
 	}
+	commands := make(chan UserCommand)
 	replies := make(chan Reply)
 	user := &User{
-		nick:    nick,
-		hash:    hash,
-		server:  server,
-		clients: make(ClientSet),
-		replies: replies,
+		nick:     nick,
+		hash:     hash,
+		server:   server,
+		clients:  make(ClientSet),
+		channels: make(ChannelSet),
+		replies:  replies,
 	}
+	go user.receiveCommands(commands)
 	go user.receiveReplies(replies)
 	return user
 }
 
+func (user *User) receiveCommands(commands <-chan UserCommand) {
+	for command := range commands {
+		log.Printf("%s %T %+v", user.Id(), command, command)
+		command.HandleUser(user)
+	}
+}
+
 // Distribute replies to clients.
 func (user *User) receiveReplies(replies <-chan Reply) {
 	for reply := range replies {
+		log.Printf("%s %T %+v", user.Id(), reply, reply)
 		for client := range user.clients {
 			client.replies <- reply
 		}
@@ -82,8 +99,11 @@ func (user *User) Login(c *Client, nick string, password string) bool {
 
 	user.clients[c] = true
 	c.user = user
-	c.replies <- RplNick(c, user.nick)
-	// TODO join channels
+	for channel := range user.channels {
+		channel.GetTopic(c)
+		c.replies <- RplNamReply(channel)
+		c.replies <- RplEndOfNames(channel.server)
+	}
 	return true
 }
 
@@ -98,3 +118,15 @@ func (user *User) LogoutClient(c *Client) bool {
 func (user *User) HasClients() bool {
 	return len(user.clients) > 0
 }
+
+func (user *User) Replies() chan<- Reply {
+	return user.replies
+}
+
+//
+// commands
+//
+
+func (m *PrivMsgCommand) HandleUser(user *User) {
+	user.replies <- RplPrivMsg(m.Client(), user, m.message)
+}