diff --git a/lib/lib.go b/lib/lib.go
index 34e8b74..d1413eb 100644
--- a/lib/lib.go
+++ b/lib/lib.go
@@ -47,8 +47,11 @@ type Context interface {
 }
 
 type Address interface {
+	Url() string
 	Service() string
-	Send(Context, Message)
+	Interaction() (string, string)
+	SetUrl(string)
+	SetInteraction(string, string)
 }
 
 type Message interface {
diff --git a/lib/message/message.go b/lib/message/message.go
index 2650eaf..a24593e 100644
--- a/lib/message/message.go
+++ b/lib/message/message.go
@@ -1,6 +1,11 @@
 package message
 
-import "git.sr.ht/~cco/go-scopes/lib"
+import (
+	"fmt"
+	"strings"
+
+	"git.sr.ht/~cco/go-scopes/lib"
+)
 
 // Message implementation(s)
 
@@ -23,19 +28,56 @@ var Quit = StrMessage("quit")
 // Address implementation
 
 type address struct {
-	service string
+	url, srv, sid, iid string
+}
+
+func (addr *address) String() string {
+	return fmt.Sprintf("%s#%s/%s/%s", addr.url, addr.srv, addr.sid, addr.iid)
+}
+
+func (addr *address) Url() string {
+	return addr.url
 }
 
 func (addr *address) Service() string {
-	return addr.service
+	return addr.srv
 }
 
-func (addr *address) Send(ctx lib.Context, msg lib.Message) {
-	lib.Send(ctx, addr, msg)
+func (addr *address) Interaction() (sid, iid string) {
+	return addr.sid, addr.iid
+}
+
+func (addr *address) SetUrl(url string) {
+	addr.url = url
+}
+
+func (addr *address) SetInteraction(sid, iid string) {
+	addr.sid = sid
+	addr.iid = iid
 }
 
 func SimpleAddress(srv string) *address {
 	return &address{
-		service: srv,
+		srv: srv,
 	}
 }
+
+func ParseAddress(astr string) *address {
+	addr := address{}
+	p1 := strings.SplitN(astr, "#", 2)
+	s1 := p1[0]
+	s2 := s1
+	if len(p1) > 1 {
+		addr.url = s1
+		s2 = p1[1]
+	}
+	p2 := strings.Split(s2, "/")
+	addr.srv = p2[0]
+	if len(p2) > 1 {
+		addr.sid = p2[1]
+		if len(p2) > 2 {
+			addr.iid = p2[2]
+		}
+	}
+	return &addr
+}
diff --git a/testing/testing.go b/testing/testing.go
index 7b0c0d2..0ffd76d 100644
--- a/testing/testing.go
+++ b/testing/testing.go
@@ -55,12 +55,12 @@ func (t *T) TearDownApp() {
 	// give actors time to recieve all messages:
 	time.Sleep(100 * time.Millisecond)
 	//t.Check()
-	message.SimpleAddress("testing").Send(t.Ctx, message.Quit)
+	lib.Send(t.Ctx, message.SimpleAddress("testing"), message.Quit)
 	t.Ctx.WaitGroup().Wait()
 	//t.AssertNoUncheckedMessages()
 }
 
-func (t *T) LogCount(pr bool) int {
+func (t *T) LogCheck(pr bool) int {
 	count := 0
 	f, _ := os.Open("log/scopes.log")
 	defer f.Close()
diff --git a/tests/scopes_test.go b/tests/scopes_test.go
index 0a5353c..fb7108c 100644
--- a/tests/scopes_test.go
+++ b/tests/scopes_test.go
@@ -11,7 +11,7 @@ import (
 	"git.sr.ht/~cco/go-scopes/tests/etc"
 )
 
-func TestConfig(tb *tbase.T) {
+func TestScopesApp(tb *tbase.T) {
 	os.Remove("log/scopes.log") // make sure we start with a fresh log file
 	t := testing.SetUpApp(tb, etc.Config())
 	t.Run("app", AppTest)
@@ -19,7 +19,7 @@ func TestConfig(tb *tbase.T) {
 	t.Run("send", SendTest)
 	t.Run("client", ClientTest)
 	t.TearDownApp()
-	t.AssertEqual(t.LogCount(true), 12)
+	t.AssertEqual(t.LogCheck(true), 12)
 }
 
 func AppTest(t *testing.T) {
diff --git a/tests/unit_test.go b/tests/unit_test.go
new file mode 100644
index 0000000..79da687
--- /dev/null
+++ b/tests/unit_test.go
@@ -0,0 +1,35 @@
+package scopes_test
+
+import (
+	"fmt"
+	tbase "testing"
+
+	"git.sr.ht/~cco/go-scopes/lib"
+	"git.sr.ht/~cco/go-scopes/lib/message"
+	"git.sr.ht/~cco/go-scopes/testing"
+)
+
+func TestUnit(tb *tbase.T) {
+	t := testing.SetUp(tb)
+	t.Run("address", AddressTest)
+}
+
+func AddressTest(t *testing.T) {
+	var ad1 lib.Address = message.SimpleAddress("worker")
+	t.AssertEqual(fmt.Sprint(ad1), "#worker//")
+	astr := "https://scopes.cy7.eu#server/1abc/2cde"
+	var ad2 lib.Address = message.ParseAddress(astr)
+	t.AssertEqual(fmt.Sprint(ad2), astr)
+	t.AssertEqual(fmt.Sprint(message.ParseAddress("worker")), "#worker//")
+	t.AssertEqual(ad1.Url(), "")
+	t.AssertEqual(ad2.Url(), "https://scopes.cy7.eu")
+	sid, iid := ad1.Interaction()
+	t.AssertEqual(sid, "")
+	t.AssertEqual(iid, "")
+	sid, iid = ad2.Interaction()
+	t.AssertEqual(sid, "1abc")
+	t.AssertEqual(iid, "2cde")
+	ad1.SetUrl("https://scopes.cy7.eu")
+	ad1.SetInteraction("1abc", "2cde")
+	t.AssertEqual(fmt.Sprint(ad1), "https://scopes.cy7.eu#worker/1abc/2cde")
+}