diff --git a/server.go b/server.go
index 48dacda..9dd9c7f 100644
--- a/server.go
+++ b/server.go
@@ -47,7 +47,6 @@ type Server interface {
 
 type TransportLayerFactory func(
 	ip net.IP,
-	proxy string,
 	dnsResolver *net.Resolver,
 	msgMapper sip.MessageMapper,
 	logger log.Logger,
@@ -151,7 +150,7 @@ func NewServer(
 	srv.log = logger.WithFields(log.Fields{
 		"sip_server_ptr": fmt.Sprintf("%p", srv),
 	})
-	srv.tp = tpFactory(ip, "", dnsResolver, config.MsgMapper, srv.Log())
+	srv.tp = tpFactory(ip, dnsResolver, config.MsgMapper, srv.Log())
 	sipTp := &sipTransport{
 		tpl: srv.tp,
 		srv: srv,
diff --git a/sip/message.go b/sip/message.go
index 5a005f3..b82d050 100644
--- a/sip/message.go
+++ b/sip/message.go
@@ -111,6 +111,8 @@ type Message interface {
 	SetSource(src string)
 	Destination() string
 	SetDestination(dest string)
+	Proxy() string
+	SetProxy(proxy string)
 
 	IsCancel() bool
 	IsAck() bool
@@ -415,6 +417,7 @@ type message struct {
 	startLine  func() string
 	tp         string
 	src        string
+	proxy      string
 	dest       string
 	fields     log.Fields
 }
@@ -523,6 +526,18 @@ func (msg *message) SetDestination(dest string) {
 	msg.mu.Unlock()
 }
 
+func (msg *message) Proxy() string {
+	msg.mu.RLock()
+	defer msg.mu.RUnlock()
+	return msg.proxy
+}
+
+func (msg *message) SetProxy(proxy string) {
+	msg.mu.Lock()
+	msg.proxy = proxy
+	msg.mu.Unlock()
+}
+
 // Copy all headers of one type from one message to another.
 // Appending to any headers that were already there.
 func CopyHeaders(name string, from, to Message) {
diff --git a/sip/request.go b/sip/request.go
index 2d7cc95..01abdff 100644
--- a/sip/request.go
+++ b/sip/request.go
@@ -224,6 +224,10 @@ func (req *request) Source() string {
 	return fmt.Sprintf("%v:%v", host, port)
 }
 
+func (req *request) Proxy() string {
+	return req.message.Proxy()
+}
+
 func (req *request) Destination() string {
 	if dest := req.message.Destination(); dest != "" {
 		return dest
diff --git a/transport/layer.go b/transport/layer.go
index ceb4947..b5cff19 100644
--- a/transport/layer.go
+++ b/transport/layer.go
@@ -72,7 +72,6 @@ type layer struct {
 	protocols   *protocolStore
 	listenPorts map[string][]sip.Port
 	ip          net.IP
-	proxy       string
 	dnsResolver *net.Resolver
 	msgMapper   sip.MessageMapper
 
@@ -94,7 +93,6 @@ type layer struct {
 // - dnsAddr - DNS server address, default is 127.0.0.1:53
 func NewLayer(
 	ip net.IP,
-	proxy string,
 	dnsResolver *net.Resolver,
 	msgMapper sip.MessageMapper,
 	logger log.Logger,
@@ -105,7 +103,6 @@ func NewLayer(
 		ip:          ip,
 		dnsResolver: dnsResolver,
 		msgMapper:   msgMapper,
-		proxy:       proxy,
 
 		msgs:     make(chan sip.Message),
 		errs:     make(chan error),
@@ -261,8 +258,8 @@ func (tpl *layer) Send(msg sip.Message) error {
 
 		var dest string
 
-		if tpl.proxy != "" {
-			dest = tpl.proxy
+		if msg.Proxy() != "" {
+			dest = msg.Proxy()
 		} else {
 			dest = msg.Destination()
 		}
@@ -328,8 +325,8 @@ func (tpl *layer) Send(msg sip.Message) error {
 
 		var dest string
 
-		if tpl.proxy != "" {
-			dest = tpl.proxy
+		if msg.Proxy() != "" {
+			dest = msg.Proxy()
 		} else {
 			dest = msg.Destination()
 		}