diff --git a/clients.go b/clients.go
index e705b0b..9a9b355 100644
--- a/clients.go
+++ b/clients.go
@@ -104,7 +104,7 @@ func newClient(p *packets.Parser, pk *packets.ConnectPacket) *client {
 		keepalive:    pk.Keepalive,
 		cleanSession: pk.CleanSession,
 		inFlight: inFlight{
-			internal: make(map[uint16]*inFlightMessage),
+			internal: make(map[uint16]*inFlightMessage, 2),
 		},
 	}
 
diff --git a/mqtt.go b/mqtt.go
index 38cadcc..3413bd1 100644
--- a/mqtt.go
+++ b/mqtt.go
@@ -3,6 +3,7 @@ package mqtt
 import (
 	"bufio"
 	"errors"
+	"log"
 	"net"
 
 	"github.com/mochi-co/mqtt/auth"
@@ -261,6 +262,7 @@ func (s *Server) processPacket(cl *client, pk packets.Packet) error {
 		})
 		if err != nil {
 			s.closeClient(cl, true)
+			return err
 		}
 
 	case *packets.PublishPacket:
@@ -295,6 +297,7 @@ func (s *Server) processPacket(cl *client, pk packets.Packet) error {
 				err := s.writeClient(client, out)
 				if err != nil {
 					s.closeClient(client, true)
+					return err
 				}
 
 				// If QoS byte is set, save as message to inflight index so we
@@ -318,6 +321,7 @@ func (s *Server) processPacket(cl *client, pk packets.Packet) error {
 			err := s.writeClient(cl, out)
 			if err != nil {
 				s.closeClient(cl, true)
+				return err
 			}
 
 			cl.inFlight.set(out.PacketID, out)
@@ -333,6 +337,7 @@ func (s *Server) processPacket(cl *client, pk packets.Packet) error {
 			err := s.writeClient(cl, out)
 			if err != nil {
 				s.closeClient(cl, true)
+				return err
 			}
 
 			cl.inFlight.delete(msg.PacketID)
@@ -358,8 +363,10 @@ func (s *Server) processPacket(cl *client, pk packets.Packet) error {
 			PacketID:    msg.PacketID,
 			ReturnCodes: retCodes,
 		})
+
 		if err != nil {
 			s.closeClient(cl, true)
+			return err
 		}
 
 		// Publish out any retained messages matching the subscription filter.
@@ -368,7 +375,9 @@ func (s *Server) processPacket(cl *client, pk packets.Packet) error {
 			for _, pkv := range messages {
 				err := s.writeClient(cl, pkv)
 				if err != nil {
+					log.Println("write err B", err)
 					s.closeClient(cl, true)
+					return err
 				}
 			}
 		}
@@ -385,6 +394,7 @@ func (s *Server) processPacket(cl *client, pk packets.Packet) error {
 		})
 		if err != nil {
 			s.closeClient(cl, true)
+			return err
 		}
 	}
 
diff --git a/mqtt_test.go b/mqtt_test.go
index a802310..60a76ac 100644
--- a/mqtt_test.go
+++ b/mqtt_test.go
@@ -5,6 +5,7 @@ import (
 	"io/ioutil"
 	"log"
 	"net"
+	"strings"
 	"testing"
 	"time"
 
@@ -549,9 +550,38 @@ func TestServerWriteClientNilWriter(t *testing.T) {
 }
 
 func TestServerWriteClientWriteError(t *testing.T) {
+	s, r, w, cl := setupClient("zen")
+	s.clients.add(cl)
+	//
 
+	err := s.writeClient(cl, &packets.PublishPacket{})
+	require.Error(t, err)
+	w.Close()
+	r.Close()
 }
 
+/*
+func TestServerProcessPacketSubscribeWriteError(t *testing.T) {
+	s, r, w, cl := setupClient("zen")
+
+	o := make(chan error, 2)
+	go func() {
+		r.Close()
+		err := s.processPacket(cl, &packets.SubscribePacket{
+			FixedHeader: packets.FixedHeader{
+				Type: packets.Subscribe,
+			},
+			PacketID: 10,
+		})
+		o <- err
+	}()
+
+	require.Error(t, <-o)
+	close(o)
+	w.Close()
+}
+*/
+
 /*
 
  * Server Close Client
@@ -645,7 +675,7 @@ func TestServerProcessPacketPingOK(t *testing.T) {
 	r.Close()
 }
 
-func TestServerProcessPacketPingClose(t *testing.T) {
+func TestServerProcessPacketPingWriteError(t *testing.T) {
 	s, r, w, cl := setupClient("zen")
 
 	o := make(chan error, 2)
@@ -659,7 +689,7 @@ func TestServerProcessPacketPingClose(t *testing.T) {
 		})
 
 	}()
-	require.NoError(t, <-o)
+	require.Error(t, <-o)
 	require.Nil(t, cl.p.Conn)
 
 	close(o)
@@ -744,6 +774,32 @@ func TestServerProcessPacketPublishRetain(t *testing.T) {
 	r.Close()
 }
 
+func TestServerProcessPacketPublishWriteError(t *testing.T) {
+	s, r, w, cl := setupClient("zen")
+
+	s.clients.add(cl)
+	s.topics.Subscribe("a/+/c", cl.id, 0)
+	require.Nil(t, cl.inFlight.internal[1])
+
+	o := make(chan error, 2)
+	go func() {
+		r.Close()
+		err := s.processPacket(cl, &packets.PublishPacket{
+			FixedHeader: packets.FixedHeader{
+				Type: packets.Publish,
+			},
+			TopicName: "a/b/c",
+			Payload:   []byte("hello"),
+		})
+
+		o <- err
+	}()
+
+	require.Error(t, <-o)
+	close(o)
+	w.Close()
+}
+
 func TestServerProcessPacketPuback(t *testing.T) {
 	s, r, _, cl := setupClient("zen")
 
@@ -803,6 +859,28 @@ func TestServerProcessPacketPubrec(t *testing.T) {
 	r.Close()
 }
 
+func TestServerProcessPacketPubrecWriteError(t *testing.T) {
+	s, r, w, cl := setupClient("zen")
+
+	cl.inFlight.set(10, &packets.PublishPacket{PacketID: 10})
+
+	o := make(chan error, 2)
+	go func() {
+		r.Close()
+		err := s.processPacket(cl, &packets.PubrecPacket{
+			FixedHeader: packets.FixedHeader{
+				Type: packets.Pubrec,
+			},
+			PacketID: 10,
+		})
+		o <- err
+	}()
+
+	require.Error(t, <-o)
+	close(o)
+	w.Close()
+}
+
 func TestServerProcessPacketPubrel(t *testing.T) {
 	s, r, w, cl := setupClient("zen")
 
@@ -834,6 +912,28 @@ func TestServerProcessPacketPubrel(t *testing.T) {
 	r.Close()
 }
 
+func TestServerProcessPacketPubrelWriteError(t *testing.T) {
+	s, r, w, cl := setupClient("zen")
+
+	cl.inFlight.set(10, &packets.PublishPacket{PacketID: 10})
+
+	o := make(chan error, 2)
+	go func() {
+		r.Close()
+		err := s.processPacket(cl, &packets.PubrelPacket{
+			FixedHeader: packets.FixedHeader{
+				Type: packets.Pubrel,
+			},
+			PacketID: 10,
+		})
+		o <- err
+	}()
+
+	require.Error(t, <-o)
+	close(o)
+	w.Close()
+}
+
 func TestServerProcessPacketPubcomp(t *testing.T) {
 	s, r, _, cl := setupClient("zen")
 
@@ -945,6 +1045,64 @@ func TestServerProcessPacketSubscribeRetained(t *testing.T) {
 	r.Close()
 }
 
+func TestServerProcessPacketSubscribeRetainedWriteError(t *testing.T) {
+	s, r, w, cl := setupClient("zen")
+
+	s.topics.RetainMessage(&packets.PublishPacket{
+		FixedHeader: packets.FixedHeader{
+			Type:   packets.Publish,
+			Retain: true,
+		},
+		TopicName: "a/b/c",
+		Payload:   []byte("hello"),
+	})
+
+	require.Equal(t, 1, len(s.topics.Messages("a/b/c")))
+
+	o := make(chan error, 2)
+	go func() {
+		o <- s.processPacket(cl, &packets.SubscribePacket{
+			FixedHeader: packets.FixedHeader{
+				Type: packets.Subscribe,
+			},
+			PacketID: 10,
+			Topics:   []string{"a/b/c", "d/e/f"},
+			Qoss:     []byte{0, 1},
+		})
+		w.Close()
+	}()
+
+	buf := make([]byte, 4)
+	for i := 0; i < 4; i++ {
+		r.Read(buf)
+	}
+	r.Close()
+
+	require.Error(t, <-o)
+	close(o)
+	r.Close()
+}
+
+func TestServerProcessPacketSubscribeWriteError(t *testing.T) {
+	s, r, w, cl := setupClient("zen")
+
+	o := make(chan error, 2)
+	go func() {
+		r.Close()
+		err := s.processPacket(cl, &packets.SubscribePacket{
+			FixedHeader: packets.FixedHeader{
+				Type: packets.Subscribe,
+			},
+			PacketID: 10,
+		})
+		o <- err
+	}()
+
+	require.Error(t, <-o)
+	close(o)
+	w.Close()
+}
+
 func TestServerProcessPacketUnsubscribe(t *testing.T) {
 	s, r, w, cl := setupClient("zen")
 
@@ -980,3 +1138,23 @@ func TestServerProcessPacketUnsubscribe(t *testing.T) {
 	require.Empty(t, s.topics.Subscribers("a/b/c"))
 	require.Empty(t, s.topics.Subscribers("d/e/f"))
 }
+
+func TestServerProcessPacketUnsubscribeWriteError(t *testing.T) {
+	s, r, w, cl := setupClient("zen")
+
+	o := make(chan error, 2)
+	go func() {
+		r.Close()
+		err := s.processPacket(cl, &packets.UnsubscribePacket{
+			FixedHeader: packets.FixedHeader{
+				Type: packets.Unsubscribe,
+			},
+			PacketID: 10,
+		})
+		o <- err
+	}()
+
+	require.Error(t, <-o)
+	close(o)
+	w.Close()
+}