diff --git a/nip29/group.go b/nip29/group.go
index df92841..0287363 100644
--- a/nip29/group.go
+++ b/nip29/group.go
@@ -20,6 +20,18 @@ type Group struct {
 	LastMembersUpdate  nostr.Timestamp
 }
 
+func NewGroup(id string) *Group {
+	now := nostr.Now()
+	return &Group{
+		ID:                 id,
+		Name:               id,
+		Members:            make(map[string]*Role),
+		LastMetadataUpdate: now,
+		LastAdminsUpdate:   now,
+		LastMembersUpdate:  now,
+	}
+}
+
 func (group Group) ToMetadataEvent() *nostr.Event {
 	evt := &nostr.Event{
 		Kind:      nostr.KindSimpleGroupMetadata,
@@ -65,7 +77,7 @@ func (group Group) ToAdminsEvent() *nostr.Event {
 	for member, role := range group.Members {
 		if role != nil {
 			// is an admin
-			tag := make([]string, 0, 3+len(role.Permissions))
+			tag := make([]string, 3, 3+len(role.Permissions))
 			tag[0] = "p"
 			tag[1] = member
 			tag[2] = role.Name
@@ -99,13 +111,11 @@ func (group *Group) MergeInMetadataEvent(evt *nostr.Event) error {
 	if evt.Kind != nostr.KindSimpleGroupMetadata {
 		return fmt.Errorf("expected kind %d, got %d", nostr.KindSimpleGroupMetadata, evt.Kind)
 	}
-
-	if evt.CreatedAt <= group.LastMetadataUpdate {
+	if evt.CreatedAt < group.LastMetadataUpdate {
 		return fmt.Errorf("event is older than our last update (%d vs %d)", evt.CreatedAt, group.LastMetadataUpdate)
 	}
 
 	group.LastMetadataUpdate = evt.CreatedAt
-	group.ID = evt.Tags.GetD()
 	group.Name = group.ID
 
 	if tag := evt.Tags.GetFirst([]string{"name", ""}); tag != nil {
@@ -132,8 +142,7 @@ func (group *Group) MergeInAdminsEvent(evt *nostr.Event) error {
 	if evt.Kind != nostr.KindSimpleGroupAdmins {
 		return fmt.Errorf("expected kind %d, got %d", nostr.KindSimpleGroupAdmins, evt.Kind)
 	}
-
-	if evt.CreatedAt <= group.LastAdminsUpdate {
+	if evt.CreatedAt < group.LastAdminsUpdate {
 		return fmt.Errorf("event is older than our last update (%d vs %d)", evt.CreatedAt, group.LastAdminsUpdate)
 	}
 
@@ -148,6 +157,18 @@ func (group *Group) MergeInAdminsEvent(evt *nostr.Event) error {
 		if !nostr.IsValidPublicKeyHex(tag[1]) {
 			continue
 		}
+
+		role := group.Members[tag[1]]
+		if role == nil {
+			role = &Role{Name: tag[2]}
+			group.Members[tag[1]] = role
+		}
+		if role.Permissions == nil {
+			role.Permissions = make(map[Permission]struct{}, len(tag)-3)
+		}
+		for _, perm := range tag[2:] {
+			role.Permissions[Permission(perm)] = struct{}{}
+		}
 	}
 
 	return nil
@@ -157,8 +178,7 @@ func (group *Group) MergeInMembersEvent(evt *nostr.Event) error {
 	if evt.Kind != nostr.KindSimpleGroupMembers {
 		return fmt.Errorf("expected kind %d, got %d", nostr.KindSimpleGroupMembers, evt.Kind)
 	}
-
-	if evt.CreatedAt <= group.LastMembersUpdate {
+	if evt.CreatedAt < group.LastMembersUpdate {
 		return fmt.Errorf("event is older than our last update (%d vs %d)", evt.CreatedAt, group.LastMembersUpdate)
 	}
 
@@ -173,6 +193,11 @@ func (group *Group) MergeInMembersEvent(evt *nostr.Event) error {
 		if !nostr.IsValidPublicKeyHex(tag[1]) {
 			continue
 		}
+
+		_, exists := group.Members[tag[1]]
+		if !exists {
+			group.Members[tag[1]] = EmptyRole
+		}
 	}
 
 	return nil
diff --git a/nip29/nip29_test.go b/nip29/nip29_test.go
new file mode 100644
index 0000000..aecbd9c
--- /dev/null
+++ b/nip29/nip29_test.go
@@ -0,0 +1,61 @@
+package nip29
+
+import (
+	"testing"
+)
+
+const (
+	ALICE = "eadad094b75b4690e7ee7124522861b8d81d5ed92e81eb678e776d1164d1efe9"
+	BOB   = "6ac475cdf30e2006ee5142559544e86f8f1b485a9c8c1f2da467996fb7fcdfe7"
+	CAROL = "f81982b8b6ba354a1e09acfda348512ef93e5778847fb5f4b30fe6b0042f4b36"
+	DEREK = "24a049c4e5c9cff1764c312b2e0fa59a02af235b37809180b3f2c7b2ec3dbdfd"
+)
+
+func TestGroupEventBackAndForth(t *testing.T) {
+	group1 := NewGroup("xyz")
+	group1.Name = "banana"
+	group1.Private = true
+	meta1 := group1.ToMetadataEvent()
+	if meta1.Tags.GetD() != "xyz" ||
+		meta1.Tags.GetFirst([]string{"name", "banana"}) == nil ||
+		meta1.Tags.GetFirst([]string{"private"}) == nil {
+		t.Fatalf("translation of group1 to meta1data event failed")
+	}
+
+	group2 := NewGroup("abc")
+	group2.Members[ALICE] = &Role{Name: "nada", Permissions: map[Permission]struct{}{PermAddUser: {}}}
+	group2.Members[BOB] = &Role{Name: "nada", Permissions: map[Permission]struct{}{PermEditMetadata: {}}}
+	group2.Members[CAROL] = EmptyRole
+	group2.Members[DEREK] = EmptyRole
+	admins2 := group2.ToAdminsEvent()
+	if admins2.Tags.GetD() != "abc" ||
+		len(admins2.Tags) != 3 ||
+		admins2.Tags.GetFirst([]string{"p", ALICE, "nada", "add-user"}) == nil ||
+		admins2.Tags.GetFirst([]string{"p", BOB, "nada", "edit-metadata"}) == nil {
+		t.Fatalf("translation of group2 to admins event failed")
+	}
+
+	members2 := group2.ToMembersEvent()
+	if members2.Tags.GetD() != "abc" ||
+		len(members2.Tags) != 5 ||
+		members2.Tags.GetFirst([]string{"p", ALICE}) == nil ||
+		members2.Tags.GetFirst([]string{"p", BOB}) == nil ||
+		members2.Tags.GetFirst([]string{"p", CAROL}) == nil ||
+		members2.Tags.GetFirst([]string{"p", DEREK}) == nil {
+		t.Fatalf("translation of group2 to members2 event failed")
+	}
+
+	group1.MergeInMembersEvent(members2)
+	if len(group1.Members) != 4 || group1.Members[ALICE] != EmptyRole || group1.Members[DEREK] != EmptyRole {
+		t.Fatalf("merge of members2 into group1 failed")
+	}
+	group1.MergeInAdminsEvent(admins2)
+	if len(group1.Members) != 4 || group1.Members[ALICE].Name != "nada" || group1.Members[DEREK] != EmptyRole {
+		t.Fatalf("merge of admins2 into group1 failed")
+	}
+
+	group2.MergeInMetadataEvent(meta1)
+	if group2.Name != "banana" || group2.ID != "abc" {
+		t.Fatalf("merge of meta1 into group2 failed")
+	}
+}