diff --git a/cluster.go b/cluster.go
index 7291cb30..817cb90f 100644
--- a/cluster.go
+++ b/cluster.go
@@ -1,7 +1,6 @@
 package redis
 
 import (
-	"log"
 	"math/rand"
 	"sync"
 	"sync/atomic"
@@ -256,13 +255,13 @@ func (c *ClusterClient) reloadSlots() {
 
 	client, err := c.randomClient()
 	if err != nil {
-		log.Printf("redis: randomClient failed: %s", err)
+		Logger.Printf("redis: randomClient failed: %s", err)
 		return
 	}
 
 	slots, err := client.ClusterSlots().Result()
 	if err != nil {
-		log.Printf("redis: ClusterSlots failed: %s", err)
+		Logger.Printf("redis: ClusterSlots failed: %s", err)
 		return
 	}
 	c.setSlots(slots)
diff --git a/commands.go b/commands.go
index f8a80f56..a3495eea 100644
--- a/commands.go
+++ b/commands.go
@@ -2,7 +2,6 @@ package redis
 
 import (
 	"io"
-	"log"
 	"strconv"
 	"time"
 )
@@ -32,7 +31,7 @@ func usePrecise(dur time.Duration) bool {
 
 func formatMs(dur time.Duration) string {
 	if dur > 0 && dur < time.Millisecond {
-		log.Printf(
+		Logger.Printf(
 			"redis: specified duration is %s, but minimal supported value is %s",
 			dur, time.Millisecond,
 		)
@@ -42,7 +41,7 @@ func formatMs(dur time.Duration) string {
 
 func formatSec(dur time.Duration) string {
 	if dur > 0 && dur < time.Second {
-		log.Printf(
+		Logger.Printf(
 			"redis: specified duration is %s, but minimal supported value is %s",
 			dur, time.Second,
 		)
diff --git a/multi.go b/multi.go
index 0e0281d3..498951e0 100644
--- a/multi.go
+++ b/multi.go
@@ -3,7 +3,6 @@ package redis
 import (
 	"errors"
 	"fmt"
-	"log"
 )
 
 var errDiscard = errors.New("redis: Discard can be used only inside Exec")
@@ -53,7 +52,7 @@ func (c *Multi) putConn(cn *conn, err error) {
 	} else {
 		err := c.base.connPool.Put(cn)
 		if err != nil {
-			log.Printf("redis: putConn failed: %s", err)
+			Logger.Printf("redis: putConn failed: %s", err)
 		}
 	}
 }
@@ -70,7 +69,7 @@ func (c *Multi) process(cmd Cmder) {
 func (c *Multi) Close() error {
 	c.closed = true
 	if err := c.Unwatch().Err(); err != nil {
-		log.Printf("redis: Unwatch failed: %s", err)
+		Logger.Printf("redis: Unwatch failed: %s", err)
 	}
 	return c.base.Close()
 }
diff --git a/pool.go b/pool.go
index 76ba10df..af7773fd 100644
--- a/pool.go
+++ b/pool.go
@@ -3,7 +3,6 @@ package redis
 import (
 	"errors"
 	"fmt"
-	"log"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -178,7 +177,7 @@ func (p *connPool) First() *conn {
 				var err error
 				cn, err = p.replace(cn)
 				if err != nil {
-					log.Printf("redis: replace failed: %s", err)
+					Logger.Printf("redis: replace failed: %s", err)
 					continue
 				}
 			}
@@ -200,7 +199,7 @@ func (p *connPool) wait() *conn {
 				var err error
 				cn, err = p.replace(cn)
 				if err != nil {
-					log.Printf("redis: replace failed: %s", err)
+					Logger.Printf("redis: replace failed: %s", err)
 					continue
 				}
 			}
@@ -272,7 +271,7 @@ func (p *connPool) Put(cn *conn) error {
 	if cn.rd.Buffered() != 0 {
 		b, _ := cn.rd.Peek(cn.rd.Buffered())
 		err := fmt.Errorf("redis: connection has unread data: %q", b)
-		log.Print(err)
+		Logger.Print(err)
 		return p.Remove(cn, err)
 	}
 	if p.opt.getIdleTimeout() > 0 {
diff --git a/pubsub.go b/pubsub.go
index 031eb843..6baaeaf9 100644
--- a/pubsub.go
+++ b/pubsub.go
@@ -2,7 +2,6 @@ package redis
 
 import (
 	"fmt"
-	"log"
 	"net"
 	"time"
 )
@@ -239,12 +238,12 @@ func (c *PubSub) reconnect(reason error) {
 
 	if len(c.channels) > 0 {
 		if err := c.Subscribe(c.channels...); err != nil {
-			log.Printf("redis: Subscribe failed: %s", err)
+			Logger.Printf("redis: Subscribe failed: %s", err)
 		}
 	}
 	if len(c.patterns) > 0 {
 		if err := c.PSubscribe(c.patterns...); err != nil {
-			log.Printf("redis: PSubscribe failed: %s", err)
+			Logger.Printf("redis: PSubscribe failed: %s", err)
 		}
 	}
 }
@@ -269,7 +268,7 @@ func (c *PubSub) ReceiveMessage() (*Message, error) {
 					if err == nil {
 						continue
 					}
-					log.Printf("redis: PubSub.Ping failed: %s", err)
+					Logger.Printf("redis: PubSub.Ping failed: %s", err)
 				}
 			}
 
diff --git a/redis.go b/redis.go
index db22af6e..aac6fbe4 100644
--- a/redis.go
+++ b/redis.go
@@ -4,9 +4,12 @@ import (
 	"fmt"
 	"log"
 	"net"
+	"os"
 	"time"
 )
 
+var Logger = log.New(os.Stderr, "", log.LstdFlags)
+
 type baseClient struct {
 	connPool pool
 	opt      *Options
@@ -27,7 +30,7 @@ func (c *baseClient) putConn(cn *conn, err error) {
 		err = c.connPool.Put(cn)
 	}
 	if err != nil {
-		log.Printf("redis: putConn failed: %s", err)
+		Logger.Printf("redis: putConn failed: %s", err)
 	}
 }
 
diff --git a/ring.go b/ring.go
index d6bcf805..1601221b 100644
--- a/ring.go
+++ b/ring.go
@@ -3,7 +3,6 @@ package redis
 import (
 	"errors"
 	"fmt"
-	"log"
 	"sync"
 	"time"
 
@@ -202,7 +201,7 @@ func (ring *Ring) heartbeat() {
 		for _, shard := range ring.shards {
 			err := shard.Client.Ping().Err()
 			if shard.Vote(err == nil || err == errPoolTimeout) {
-				log.Printf("redis: ring shard state changed: %s", shard)
+				Logger.Printf("redis: ring shard state changed: %s", shard)
 				rebalance = true
 			}
 		}
diff --git a/sentinel.go b/sentinel.go
index 7edd75f2..462c9d36 100644
--- a/sentinel.go
+++ b/sentinel.go
@@ -3,7 +3,6 @@ package redis
 import (
 	"errors"
 	"fmt"
-	"log"
 	"net"
 	"strings"
 	"sync"
@@ -145,11 +144,11 @@ func (d *sentinelFailover) MasterAddr() (string, error) {
 	if d._sentinel != nil {
 		addr, err := d._sentinel.GetMasterAddrByName(d.masterName).Result()
 		if err != nil {
-			log.Printf("redis-sentinel: GetMasterAddrByName %q failed: %s", d.masterName, err)
+			Logger.Printf("redis-sentinel: GetMasterAddrByName %q failed: %s", d.masterName, err)
 			d.resetSentinel()
 		} else {
 			addr := net.JoinHostPort(addr[0], addr[1])
-			log.Printf("redis-sentinel: %q addr is %s", d.masterName, addr)
+			Logger.Printf("redis-sentinel: %q addr is %s", d.masterName, addr)
 			return addr, nil
 		}
 	}
@@ -168,7 +167,7 @@ func (d *sentinelFailover) MasterAddr() (string, error) {
 		})
 		masterAddr, err := sentinel.GetMasterAddrByName(d.masterName).Result()
 		if err != nil {
-			log.Printf("redis-sentinel: GetMasterAddrByName %q failed: %s", d.masterName, err)
+			Logger.Printf("redis-sentinel: GetMasterAddrByName %q failed: %s", d.masterName, err)
 			sentinel.Close()
 			continue
 		}
@@ -178,7 +177,7 @@ func (d *sentinelFailover) MasterAddr() (string, error) {
 
 		d.setSentinel(sentinel)
 		addr := net.JoinHostPort(masterAddr[0], masterAddr[1])
-		log.Printf("redis-sentinel: %q addr is %s", d.masterName, addr)
+		Logger.Printf("redis-sentinel: %q addr is %s", d.masterName, addr)
 		return addr, nil
 	}
 
@@ -194,7 +193,7 @@ func (d *sentinelFailover) setSentinel(sentinel *sentinelClient) {
 func (d *sentinelFailover) discoverSentinels(sentinel *sentinelClient) {
 	sentinels, err := sentinel.Sentinels(d.masterName).Result()
 	if err != nil {
-		log.Printf("redis-sentinel: Sentinels %q failed: %s", d.masterName, err)
+		Logger.Printf("redis-sentinel: Sentinels %q failed: %s", d.masterName, err)
 		return
 	}
 	for _, sentinel := range sentinels {
@@ -204,7 +203,7 @@ func (d *sentinelFailover) discoverSentinels(sentinel *sentinelClient) {
 			if key == "name" {
 				sentinelAddr := vals[i+1].(string)
 				if !contains(d.sentinelAddrs, sentinelAddr) {
-					log.Printf(
+					Logger.Printf(
 						"redis-sentinel: discovered new %q sentinel: %s",
 						d.masterName, sentinelAddr,
 					)
@@ -232,7 +231,7 @@ func (d *sentinelFailover) closeOldConns(newMaster string) {
 				"redis-sentinel: closing connection to the old master %s",
 				cn.RemoteAddr(),
 			)
-			log.Print(err)
+			Logger.Print(err)
 			d.pool.Remove(cn, err)
 		} else {
 			cnsToPut = append(cnsToPut, cn)
@@ -250,7 +249,7 @@ func (d *sentinelFailover) listen() {
 		if pubsub == nil {
 			pubsub = d._sentinel.PubSub()
 			if err := pubsub.Subscribe("+switch-master"); err != nil {
-				log.Printf("redis-sentinel: Subscribe failed: %s", err)
+				Logger.Printf("redis-sentinel: Subscribe failed: %s", err)
 				d.lock.Lock()
 				d.resetSentinel()
 				d.lock.Unlock()
@@ -260,7 +259,7 @@ func (d *sentinelFailover) listen() {
 
 		msgIface, err := pubsub.Receive()
 		if err != nil {
-			log.Printf("redis-sentinel: Receive failed: %s", err)
+			Logger.Printf("redis-sentinel: Receive failed: %s", err)
 			pubsub.Close()
 			return
 		}
@@ -271,23 +270,23 @@ func (d *sentinelFailover) listen() {
 			case "+switch-master":
 				parts := strings.Split(msg.Payload, " ")
 				if parts[0] != d.masterName {
-					log.Printf("redis-sentinel: ignore new %s addr", parts[0])
+					Logger.Printf("redis-sentinel: ignore new %s addr", parts[0])
 					continue
 				}
 				addr := net.JoinHostPort(parts[3], parts[4])
-				log.Printf(
+				Logger.Printf(
 					"redis-sentinel: new %q addr is %s",
 					d.masterName, addr,
 				)
 
 				d.closeOldConns(addr)
 			default:
-				log.Printf("redis-sentinel: unsupported message: %s", msg)
+				Logger.Printf("redis-sentinel: unsupported message: %s", msg)
 			}
 		case *Subscription:
 			// Ignore.
 		default:
-			log.Printf("redis-sentinel: unsupported message: %s", msgIface)
+			Logger.Printf("redis-sentinel: unsupported message: %s", msgIface)
 		}
 	}
 }