diff --git a/.travis.yml b/.travis.yml
index b35dfc1..014a722 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,10 +1,9 @@
 language: go
 go:
   - 1.5
-before_install:
-  - go get golang.org/x/crypto/ssh/terminal
+  - 1.7
 script:
   - GOOS=windows go install github.com/chzyer/readline/example/...
   - GOOS=linux go install github.com/chzyer/readline/example/...
   - GOOS=darwin go install github.com/chzyer/readline/example/...
-  - go test -v
+  - go test -race -v
diff --git a/readline_test.go b/readline_test.go
new file mode 100644
index 0000000..34a5a3b
--- /dev/null
+++ b/readline_test.go
@@ -0,0 +1,27 @@
+package readline
+
+import (
+	"testing"
+	"time"
+)
+
+func TestRace(t *testing.T) {
+	rl, err := NewEx(&Config{})
+	if err != nil {
+		t.Fatal(err)
+		return
+	}
+
+	go func() {
+		for range time.Tick(time.Millisecond) {
+			rl.SetPrompt("hello")
+		}
+	}()
+
+	go func() {
+		time.Sleep(100 * time.Millisecond)
+		rl.Close()
+	}()
+
+	rl.Readline()
+}
diff --git a/runebuf.go b/runebuf.go
index 545bc83..1b2a5d0 100644
--- a/runebuf.go
+++ b/runebuf.go
@@ -33,11 +33,15 @@ type RuneBuffer struct {
 }
 
 func (r *RuneBuffer) OnWidthChange(newWidth int) {
+	r.Lock()
 	r.width = newWidth
+	r.Unlock()
 }
 
 func (r *RuneBuffer) Backup() {
+	r.Lock()
 	r.bck = &runeBufferBck{r.buf, r.idx}
+	r.Unlock()
 }
 
 func (r *RuneBuffer) Restore() {
@@ -62,15 +66,21 @@ func NewRuneBuffer(w io.Writer, prompt string, cfg *Config, width int) *RuneBuff
 }
 
 func (r *RuneBuffer) SetConfig(cfg *Config) {
+	r.Lock()
 	r.cfg = cfg
 	r.interactive = cfg.useInteractive()
+	r.Unlock()
 }
 
 func (r *RuneBuffer) SetMask(m rune) {
+	r.Lock()
 	r.cfg.MaskRune = m
+	r.Unlock()
 }
 
 func (r *RuneBuffer) CurrentWidth(x int) int {
+	r.Lock()
+	defer r.Unlock()
 	return runes.WidthAll(r.buf[:x])
 }
 
@@ -86,6 +96,9 @@ func (r *RuneBuffer) promptLen() int {
 }
 
 func (r *RuneBuffer) RuneSlice(i int) []rune {
+	r.Lock()
+	defer r.Unlock()
+
 	if i > 0 {
 		rs := make([]rune, i)
 		copy(rs, r.buf[r.idx:r.idx+i])
@@ -97,16 +110,22 @@ func (r *RuneBuffer) RuneSlice(i int) []rune {
 }
 
 func (r *RuneBuffer) Runes() []rune {
+	r.Lock()
 	newr := make([]rune, len(r.buf))
 	copy(newr, r.buf)
+	r.Unlock()
 	return newr
 }
 
 func (r *RuneBuffer) Pos() int {
+	r.Lock()
+	defer r.Unlock()
 	return r.idx
 }
 
 func (r *RuneBuffer) Len() int {
+	r.Lock()
+	defer r.Unlock()
 	return len(r.buf)
 }
 
@@ -154,6 +173,8 @@ func (r *RuneBuffer) MoveForward() {
 }
 
 func (r *RuneBuffer) IsCursorInEnd() bool {
+	r.Lock()
+	defer r.Unlock()
 	return r.idx == len(r.buf)
 }
 
@@ -382,6 +403,12 @@ func (r *RuneBuffer) getSplitByLine(rs []rune) []string {
 }
 
 func (r *RuneBuffer) IdxLine(width int) int {
+	r.Lock()
+	defer r.Unlock()
+	return r.idxLine(width)
+}
+
+func (r *RuneBuffer) idxLine(width int) int {
 	if width == 0 {
 		return 0
 	}
@@ -404,7 +431,7 @@ func (r *RuneBuffer) Refresh(f func()) {
 		return
 	}
 
-	r.Clean()
+	r.clean()
 	if f != nil {
 		f()
 	}
@@ -527,10 +554,16 @@ func (r *RuneBuffer) cleanOutput(w io.Writer, idxLine int) {
 }
 
 func (r *RuneBuffer) Clean() {
-	r.clean(r.IdxLine(r.width))
+	r.Lock()
+	r.clean()
+	r.Unlock()
 }
 
-func (r *RuneBuffer) clean(idxLine int) {
+func (r *RuneBuffer) clean() {
+	r.cleanWithIdxLine(r.idxLine(r.width))
+}
+
+func (r *RuneBuffer) cleanWithIdxLine(idxLine int) {
 	if r.hadClean || !r.interactive {
 		return
 	}