diff --git a/h2quic/server_test.go b/h2quic/server_test.go
index 67799f1a..a3e642ce 100644
--- a/h2quic/server_test.go
+++ b/h2quic/server_test.go
@@ -38,6 +38,9 @@ func (s *mockSession) AcceptStream() (utils.Stream, error) {
 func (s *mockSession) OpenStream() (utils.Stream, error) {
 	panic("not implemented")
 }
+func (s *mockSession) OpenStreamSync() (utils.Stream, error) {
+	panic("not implemented")
+}
 func (s *mockSession) Close(e error) error {
 	s.closed = true
 	s.closedWithError = e
diff --git a/interface.go b/interface.go
index 7d7a1300..c8b1af96 100644
--- a/interface.go
+++ b/interface.go
@@ -15,9 +15,8 @@ type Session interface {
 	// guaranteed to return the smallest unopened stream
 	// special error for "too many streams, retry later"
 	OpenStream() (utils.Stream, error)
-	// TODO: implement this
 	// blocks until a new stream can be opened, if the maximum number of stream is opened
-	// OpenStreamSync() (utils.Stream, error)
+	OpenStreamSync() (utils.Stream, error)
 	RemoteAddr() net.Addr
 	Close(error) error
 }
diff --git a/server_test.go b/server_test.go
index 546048e0..dc867e93 100644
--- a/server_test.go
+++ b/server_test.go
@@ -38,6 +38,9 @@ func (s *mockSession) AcceptStream() (utils.Stream, error) {
 func (s *mockSession) OpenStream() (utils.Stream, error) {
 	return &stream{streamID: 1337}, nil
 }
+func (s *mockSession) OpenStreamSync() (utils.Stream, error) {
+	panic("not implemented")
+}
 func (s *mockSession) RemoteAddr() net.Addr {
 	panic("not implemented")
 }
diff --git a/session.go b/session.go
index c49d5625..17555d96 100644
--- a/session.go
+++ b/session.go
@@ -681,6 +681,10 @@ func (s *session) OpenStream() (utils.Stream, error) {
 	return s.streamsMap.OpenStream()
 }
 
+func (s *session) OpenStreamSync() (utils.Stream, error) {
+	return s.streamsMap.OpenStreamSync()
+}
+
 func (s *session) queueResetStreamFrame(id protocol.StreamID, offset protocol.ByteCount) {
 	s.packer.QueueControlFrameForNextPacket(&frames.RstStreamFrame{
 		StreamID:   id,
diff --git a/session_test.go b/session_test.go
index 7a77c8f9..c25f028e 100644
--- a/session_test.go
+++ b/session_test.go
@@ -1240,6 +1240,13 @@ var _ = Describe("Session", func() {
 			_, ok := str.(utils.Stream)
 			Expect(ok).To(BeFalse())
 		})
+
+		// all relevant tests for this are in the streamsMap
+		It("opens streams synchronously", func() {
+			str, err := sess.OpenStreamSync()
+			Expect(err).ToNot(HaveOccurred())
+			Expect(str).ToNot(BeNil())
+		})
 	})
 
 	Context("counting streams", func() {