diff --git a/connection.go b/connection.go
index 233aba9..131a75b 100644
--- a/connection.go
+++ b/connection.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"net"
 	"strconv"
+	"sync"
 	"time"
 )
 
@@ -75,6 +76,7 @@ type LocalConnection struct {
 	finished        <-chan struct{} // closed to signal that actorLoop has finished
 	senders         *gossipSenders
 	logger          Logger
+	mu              *sync.RWMutex
 }
 
 // If the connection is successful, it will end up in the local peer's
@@ -94,6 +96,7 @@ func startLocalConnection(connRemote *remoteConnection, tcpConn *net.TCPConn, ro
 		errorChan:        errorChan,
 		finished:         finished,
 		logger:           logger,
+		mu:               &sync.RWMutex{},
 	}
 	conn.senders = newGossipSenders(conn, finished)
 	go conn.run(errorChan, finished, acceptNewPeer)
@@ -119,6 +122,8 @@ func (conn *LocalConnection) breakTie(dupConn ourConnection) connectionTieBreak
 // Established returns true if the connection is established.
 // TODO(pb): data race?
 func (conn *LocalConnection) isEstablished() bool {
+	defer conn.mu.RUnlock()
+	conn.mu.RLock()
 	return conn.established
 }
 
@@ -355,7 +360,9 @@ func (conn *LocalConnection) actorLoop(errorChan <-chan error) (err error) {
 			case <-conn.heartbeatTCP.C:
 				err = conn.sendSimpleProtocolMsg(ProtocolHeartbeat)
 			case <-fwdEstablishedChan:
+				conn.mu.Lock()
 				conn.established = true
+				conn.mu.Unlock()
 				fwdEstablishedChan = nil
 				conn.router.Ourself.doConnectionEstablished(conn)
 			case err = <-errorChan:
diff --git a/peer.go b/peer.go
index 22b4138..6a6e83d 100644
--- a/peer.go
+++ b/peer.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"sort"
 	"strconv"
+	"sync"
 )
 
 // Peer is a local representation of a peer, including connections to other
@@ -15,6 +16,7 @@ type Peer struct {
 	peerSummary
 	localRefCount uint64 // maintained by Peers
 	connections   map[PeerName]Connection
+	mu            *sync.RWMutex
 }
 
 type peerSummary struct {
@@ -42,6 +44,7 @@ func newPeerFromSummary(summary peerSummary) *Peer {
 		Name:        PeerNameFromBin(summary.NameByte),
 		peerSummary: summary,
 		connections: make(map[PeerName]Connection),
+		mu:          &sync.RWMutex{},
 	}
 }
 
@@ -62,6 +65,8 @@ func newPeerPlaceholder(name PeerName) *Peer {
 
 // String returns the peer name and nickname.
 func (peer *Peer) String() string {
+	defer peer.mu.RUnlock()
+	peer.mu.RLock()
 	return fmt.Sprint(peer.Name, "(", peer.NickName, ")")
 }
 
diff --git a/peers.go b/peers.go
index 1190450..ce3b3b5 100644
--- a/peers.go
+++ b/peers.go
@@ -501,6 +501,7 @@ func (peers *Peers) applyDecodedUpdate(decodedUpdate []*Peer, decodedConns [][]c
 							(!newPeer.HasShortID || peer.HasShortID)))) {
 				continue
 			}
+			peer.mu.Lock()
 			peer.Version = newPeer.Version
 			peer.UID = newPeer.UID
 			peer.NickName = newPeer.NickName
@@ -512,6 +513,7 @@ func (peers *Peers) applyDecodedUpdate(decodedUpdate []*Peer, decodedConns [][]c
 				peer.HasShortID = newPeer.HasShortID
 				peers.addByShortID(peer, pending)
 			}
+			peer.mu.Unlock()
 			newUpdate[name] = struct{}{}
 		}
 	}