diff --git a/handshake/crypto_setup_client.go b/handshake/crypto_setup_client.go
index a45dd670..9acde21b 100644
--- a/handshake/crypto_setup_client.go
+++ b/handshake/crypto_setup_client.go
@@ -170,6 +170,18 @@ func (h *cryptoSetupClient) getTags() map[Tag][]byte {
 	binary.LittleEndian.PutUint32(versionTag, protocol.VersionNumberToTag(h.version))
 	tags[TagVER] = versionTag
 
+	if len(h.stk) > 0 {
+		tags[TagSTK] = h.stk
+	}
+
+	if len(h.sno) > 0 {
+		tags[TagSNO] = h.sno
+	}
+
+	if h.serverConfig != nil {
+		tags[TagSCID] = h.serverConfig.ID
+	}
+
 	return tags
 }
 
diff --git a/handshake/crypto_setup_client_test.go b/handshake/crypto_setup_client_test.go
index 3c798de9..2943e97c 100644
--- a/handshake/crypto_setup_client_test.go
+++ b/handshake/crypto_setup_client_test.go
@@ -106,6 +106,32 @@ var _ = Describe("Crypto setup", func() {
 			Expect(tags[TagPDMD]).To(Equal([]byte("X509")))
 			Expect(tags[TagVER]).To(Equal([]byte("Q036")))
 		})
+
+		It("includes the server config id, if available", func() {
+			id := []byte("foobar")
+			cs.serverConfig = &serverConfigClient{ID: id}
+			tags := cs.getTags()
+			Expect(tags[TagSCID]).To(Equal(id))
+		})
+
+		It("includes the source address token, if available", func() {
+			cs.stk = []byte("sourceaddresstoken")
+			tags := cs.getTags()
+			Expect(tags[TagSTK]).To(Equal(cs.stk))
+		})
+
+		It("includes the server nonce, if available", func() {
+			cs.sno = []byte("foobar")
+			tags := cs.getTags()
+			Expect(tags[TagSNO]).To(Equal(cs.sno))
+		})
+
+		It("doesn't include optional values, if not available", func() {
+			tags := cs.getTags()
+			Expect(tags).ToNot(HaveKey(TagSCID))
+			Expect(tags).ToNot(HaveKey(TagSNO))
+			Expect(tags).ToNot(HaveKey(TagSTK))
+		})
 	})
 
 	Context("Diversification Nonces", func() {