diff --git a/packet_packer.go b/packet_packer.go
index 98d91bf6..27696501 100644
--- a/packet_packer.go
+++ b/packet_packer.go
@@ -130,7 +130,7 @@ func (p *packetPacker) packPacket(stopWaitingFrame *frames.StopWaitingFrame, con
 	}
 
 	var raw bytes.Buffer
-	if err := responsePublicHeader.WritePublicHeader(&raw); err != nil {
+	if err := responsePublicHeader.WritePublicHeader(&raw, p.version); err != nil {
 		return nil, err
 	}
 
diff --git a/public_header.go b/public_header.go
index 5526f197..37e85c42 100644
--- a/public_header.go
+++ b/public_header.go
@@ -29,10 +29,11 @@ type publicHeader struct {
 	QuicVersion          uint32
 	PacketNumberLen      protocol.PacketNumberLen
 	PacketNumber         protocol.PacketNumber
+	DiversificationNonce []byte
 }
 
 // WritePublicHeader writes a public header
-func (h *publicHeader) WritePublicHeader(b *bytes.Buffer) error {
+func (h *publicHeader) WritePublicHeader(b *bytes.Buffer, version protocol.VersionNumber) error {
 	publicFlagByte := uint8(0x00)
 	if h.VersionFlag && h.ResetFlag {
 		return errResetAndVersionFlagSet
@@ -44,8 +45,17 @@ func (h *publicHeader) WritePublicHeader(b *bytes.Buffer) error {
 		publicFlagByte |= 0x02
 	}
 	if !h.TruncateConnectionID {
-		// TODO: Change this once we support version 33 properly
-		publicFlagByte |= 0x0c
+		if version < protocol.VersionNumber(33) {
+			publicFlagByte |= 0x0c
+		} else {
+			publicFlagByte |= 0x08
+		}
+	}
+	if len(h.DiversificationNonce) > 0 {
+		if len(h.DiversificationNonce) != 32 {
+			return errors.New("invalid diversification nonce length")
+		}
+		publicFlagByte |= 0x04
 	}
 
 	if !h.ResetFlag && !h.VersionFlag {
@@ -67,6 +77,10 @@ func (h *publicHeader) WritePublicHeader(b *bytes.Buffer) error {
 		utils.WriteUint64(b, uint64(h.ConnectionID))
 	}
 
+	if len(h.DiversificationNonce) > 0 {
+		b.Write(h.DiversificationNonce)
+	}
+
 	if !h.ResetFlag && !h.VersionFlag {
 		switch h.PacketNumberLen {
 		case protocol.PacketNumberLen1:
diff --git a/public_header_test.go b/public_header_test.go
index 21b6bd75..7826acc9 100644
--- a/public_header_test.go
+++ b/public_header_test.go
@@ -84,7 +84,7 @@ var _ = Describe("Public Header", func() {
 				PacketNumber:    2,
 				PacketNumberLen: protocol.PacketNumberLen6,
 			}
-			hdr.WritePublicHeader(b)
+			hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 			Expect(b.Bytes()).To(Equal([]byte{0x38 | 0x04, 0xf6, 0x19, 0x86, 0x66, 0x9b, 0x9f, 0xfa, 0x4c, 2, 0, 0, 0, 0, 0}))
 		})
 
@@ -96,7 +96,7 @@ var _ = Describe("Public Header", func() {
 				PacketNumber:    2,
 				PacketNumberLen: protocol.PacketNumberLen6,
 			}
-			hdr.WritePublicHeader(b)
+			hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 			// must be the first assertion
 			Expect(b.Len()).To(Equal(1 + 8)) // 1 FlagByte + 8 ConnectionID
 			firstByte, _ := b.ReadByte()
@@ -111,7 +111,7 @@ var _ = Describe("Public Header", func() {
 				PacketNumber:    2,
 				PacketNumberLen: protocol.PacketNumberLen6,
 			}
-			hdr.WritePublicHeader(b)
+			hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 			// must be the first assertion
 			Expect(b.Len()).To(Equal(1 + 8)) // 1 FlagByte + 8 ConnectionID
 			firstByte, _ := b.ReadByte()
@@ -127,7 +127,7 @@ var _ = Describe("Public Header", func() {
 				PacketNumber:    2,
 				PacketNumberLen: protocol.PacketNumberLen6,
 			}
-			err := hdr.WritePublicHeader(b)
+			err := hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 			Expect(err).To(MatchError(errResetAndVersionFlagSet))
 		})
 
@@ -139,11 +139,40 @@ var _ = Describe("Public Header", func() {
 				PacketNumberLen:      protocol.PacketNumberLen6,
 				PacketNumber:         1,
 			}
-			err := hdr.WritePublicHeader(b)
+			err := hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 			Expect(err).ToNot(HaveOccurred())
 			Expect(b.Bytes()).To(Equal([]byte{0x30, 0x1, 0x0, 0x0, 0x0, 0x0, 0x0}))
 		})
 
+		It("writes proper v33 packets", func() {
+			b := &bytes.Buffer{}
+			hdr := publicHeader{
+				ConnectionID:    0x4cfa9f9b668619f6,
+				PacketNumber:    1,
+				PacketNumberLen: protocol.PacketNumberLen1,
+			}
+			err := hdr.WritePublicHeader(b, protocol.VersionNumber(33))
+			Expect(err).ToNot(HaveOccurred())
+			Expect(b.Bytes()).To(Equal([]byte{0x08, 0xf6, 0x19, 0x86, 0x66, 0x9b, 0x9f, 0xfa, 0x4c, 0x01}))
+		})
+
+		It("writes diversification nonces", func() {
+			b := &bytes.Buffer{}
+			hdr := publicHeader{
+				ConnectionID:         0x4cfa9f9b668619f6,
+				PacketNumber:         1,
+				PacketNumberLen:      protocol.PacketNumberLen1,
+				DiversificationNonce: bytes.Repeat([]byte{1}, 32),
+			}
+			err := hdr.WritePublicHeader(b, protocol.VersionNumber(33))
+			Expect(err).ToNot(HaveOccurred())
+			Expect(b.Bytes()).To(Equal([]byte{
+				0x0c, 0xf6, 0x19, 0x86, 0x66, 0x9b, 0x9f, 0xfa, 0x4c,
+				1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+				0x01,
+			}))
+		})
+
 		Context("GetLength", func() {
 			It("errors when calling GetLength for Version Negotiation packets", func() {
 				hdr := publicHeader{VersionFlag: true}
@@ -208,7 +237,7 @@ var _ = Describe("Public Header", func() {
 					ConnectionID: 0x4cfa9f9b668619f6,
 					PacketNumber: 0xDECAFBAD,
 				}
-				err := hdr.WritePublicHeader(b)
+				err := hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 				Expect(err).To(MatchError(errPacketNumberLenNotSet))
 			})
 
@@ -219,7 +248,7 @@ var _ = Describe("Public Header", func() {
 					PacketNumber:    0xDECAFBAD,
 					PacketNumberLen: protocol.PacketNumberLen1,
 				}
-				err := hdr.WritePublicHeader(b)
+				err := hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 				Expect(err).ToNot(HaveOccurred())
 				Expect(b.Bytes()).To(Equal([]byte{0x08 | 0x04, 0xf6, 0x19, 0x86, 0x66, 0x9b, 0x9f, 0xfa, 0x4c, 0xAD}))
 			})
@@ -231,7 +260,7 @@ var _ = Describe("Public Header", func() {
 					PacketNumber:    0xDECAFBAD,
 					PacketNumberLen: protocol.PacketNumberLen2,
 				}
-				err := hdr.WritePublicHeader(b)
+				err := hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 				Expect(err).ToNot(HaveOccurred())
 				Expect(b.Bytes()).To(Equal([]byte{0x18 | 0x04, 0xf6, 0x19, 0x86, 0x66, 0x9b, 0x9f, 0xfa, 0x4c, 0xAD, 0xFB}))
 			})
@@ -243,7 +272,7 @@ var _ = Describe("Public Header", func() {
 					PacketNumber:    0x13DECAFBAD,
 					PacketNumberLen: protocol.PacketNumberLen4,
 				}
-				err := hdr.WritePublicHeader(b)
+				err := hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 				Expect(err).ToNot(HaveOccurred())
 				Expect(b.Bytes()).To(Equal([]byte{0x28 | 0x04, 0xf6, 0x19, 0x86, 0x66, 0x9b, 0x9f, 0xfa, 0x4c, 0xAD, 0xFB, 0xCA, 0xDE}))
 			})
@@ -255,7 +284,7 @@ var _ = Describe("Public Header", func() {
 					PacketNumber:    0xBE1337DECAFBAD,
 					PacketNumberLen: protocol.PacketNumberLen6,
 				}
-				err := hdr.WritePublicHeader(b)
+				err := hdr.WritePublicHeader(b, protocol.VersionNumber(32))
 				Expect(err).ToNot(HaveOccurred())
 				Expect(b.Bytes()).To(Equal([]byte{0x38 | 0x04, 0xf6, 0x19, 0x86, 0x66, 0x9b, 0x9f, 0xfa, 0x4c, 0xAD, 0xFB, 0xCA, 0xDE, 0x37, 0x13}))
 			})
diff --git a/server.go b/server.go
index 89e9b8bc..f5c1aab6 100644
--- a/server.go
+++ b/server.go
@@ -167,7 +167,8 @@ func composeVersionNegotiation(connectionID protocol.ConnectionID) []byte {
 		PacketNumber: 1,
 		VersionFlag:  true,
 	}
-	err := responsePublicHeader.WritePublicHeader(fullReply)
+	// TODO: Update version number
+	err := responsePublicHeader.WritePublicHeader(fullReply, protocol.VersionNumber(32))
 	if err != nil {
 		utils.Errorf("error composing version negotiation packet: %s", err.Error())
 	}