diff --git a/client/client.go b/client/client.go
index 2f12c11..b4be8e9 100644
--- a/client/client.go
+++ b/client/client.go
@@ -217,7 +217,10 @@ type handleOrError struct {
 }
 
 func (client *Client) do(funcname string, data []byte,
-	flag uint32, h ResponseHandler) (handle string, err error) {
+	flag uint32, h ResponseHandler, id string) (handle string, err error) {
+	if len(id) == 0 {
+		return "", ErrInvalidId
+	}
 	if client.conn == nil {
 		return "", ErrLostConn
 	}
@@ -233,7 +236,6 @@ func (client *Client) do(funcname string, data []byte,
 		handle = resp.Handle
 		result <- handleOrError{handle, nil}
 	}, h)
-	id := IdGen.Id()
 	req := getJob(id, []byte(funcname), data)
 	req.DataType = flag
 	if err = client.write(req); err != nil {
@@ -255,17 +257,7 @@ func (client *Client) do(funcname string, data []byte,
 // flag can be set to: JobLow, JobNormal and JobHigh
 func (client *Client) Do(funcname string, data []byte,
 	flag byte, h ResponseHandler) (handle string, err error) {
-	var datatype uint32
-	switch flag {
-	case JobLow:
-		datatype = dtSubmitJobLow
-	case JobHigh:
-		datatype = dtSubmitJobHigh
-	default:
-		datatype = dtSubmitJob
-	}
-
-	handle, err = client.do(funcname, data, datatype, h)
+	handle, err = client.DoWithId(funcname, data, flag, h, IdGen.Id())
 	return
 }
 
@@ -273,19 +265,7 @@ func (client *Client) Do(funcname string, data []byte,
 // flag can be set to: JobLow, JobNormal and JobHigh
 func (client *Client) DoBg(funcname string, data []byte,
 	flag byte) (handle string, err error) {
-	if client.conn == nil {
-		return "", ErrLostConn
-	}
-	var datatype uint32
-	switch flag {
-	case JobLow:
-		datatype = dtSubmitJobLowBg
-	case JobHigh:
-		datatype = dtSubmitJobHighBg
-	default:
-		datatype = dtSubmitJobBg
-	}
-	handle, err = client.do(funcname, data, datatype, nil)
+	handle, err = client.DoBgWithId(funcname, data, flag, IdGen.Id())
 	return
 }
 
@@ -341,3 +321,40 @@ func (client *Client) Close() (err error) {
 	}
 	return
 }
+
+// Call the function and get a response.
+// flag can be set to: JobLow, JobNormal and JobHigh
+func (client *Client) DoWithId(funcname string, data []byte,
+	flag byte, h ResponseHandler, id string) (handle string, err error) {
+	var datatype uint32
+	switch flag {
+	case JobLow:
+		datatype = dtSubmitJobLow
+	case JobHigh:
+		datatype = dtSubmitJobHigh
+	default:
+		datatype = dtSubmitJob
+	}
+	handle, err = client.do(funcname, data, datatype, h, id)
+	return
+}
+
+// Call the function in background, no response needed.
+// flag can be set to: JobLow, JobNormal and JobHigh
+func (client *Client) DoBgWithId(funcname string, data []byte,
+	flag byte, id string) (handle string, err error) {
+	if client.conn == nil {
+		return "", ErrLostConn
+	}
+	var datatype uint32
+	switch flag {
+	case JobLow:
+		datatype = dtSubmitJobLowBg
+	case JobHigh:
+		datatype = dtSubmitJobHighBg
+	default:
+		datatype = dtSubmitJobBg
+	}
+	handle, err = client.do(funcname, data, datatype, nil, id)
+	return
+}
diff --git a/client/client_test.go b/client/client_test.go
index e19ea98..124bb04 100644
--- a/client/client_test.go
+++ b/client/client_test.go
@@ -1,8 +1,11 @@
 package client
 
 import (
+	"crypto/md5"
+	"encoding/hex"
 	"errors"
 	"flag"
+	"fmt"
 	"os"
 	"testing"
 	"time"
@@ -72,6 +75,42 @@ func TestClientDoBg(t *testing.T) {
 	}
 }
 
+func TestClientDoBgWithId(t *testing.T) {
+	if !runIntegrationTests {
+		t.Skip("To run this test, use: go test -integration")
+	}
+	data := []byte("abcdef")
+	hash := md5.Sum(data)
+	id := hex.EncodeToString(hash[:])
+	handle, err := client.DoBgWithId("ToUpper", data, JobLow, id)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	if handle == "" {
+		t.Error("Handle is empty.")
+	} else {
+		t.Log(handle)
+	}
+}
+
+func TestClientDoBgWithIdFailsIfNoId(t *testing.T) {
+	if !runIntegrationTests {
+		t.Skip("To run this test, use: go test -integration")
+	}
+	data := []byte("abcdef")
+	id := ""
+	_, err := client.DoBgWithId("ToUpper", data, JobLow, id)
+	if err == nil {
+		t.Error("Expecting error")
+		return
+	}
+	if err.Error() != "Invalid ID" {
+		t.Error(fmt.Sprintf("Expecting \"Invalid ID\" error, got %s.", err.Error()))
+		return
+	}
+}
+
 func TestClientDo(t *testing.T) {
 	if !runIntegrationTests {
 		t.Skip("To run this test, use: go test -integration")
@@ -98,6 +137,138 @@ func TestClientDo(t *testing.T) {
 	}
 }
 
+func TestClientDoWithId(t *testing.T) {
+	if !runIntegrationTests {
+		t.Skip("To run this test, use: go test -integration")
+	}
+	jobHandler := func(job *Response) {
+		str := string(job.Data)
+		if str == "ABCDEF" {
+			t.Log(str)
+		} else {
+			t.Errorf("Invalid data: %s", job.Data)
+		}
+		return
+	}
+	data := []byte("abcdef")
+	hash := md5.Sum(data)
+	id := hex.EncodeToString(hash[:])
+	handle, err := client.DoWithId("ToUpper", data,
+		JobLow, jobHandler, id)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	if handle == "" {
+		t.Error("Handle is empty.")
+	} else {
+		t.Log(handle)
+	}
+}
+
+func TestClientDoWithIdFailsIfNoId(t *testing.T) {
+	if !runIntegrationTests {
+		t.Skip("To run this test, use: go test -integration")
+	}
+	jobHandler := func(job *Response) {
+		str := string(job.Data)
+		if str == "ABCDEF" {
+			t.Log(str)
+		} else {
+			t.Errorf("Invalid data: %s", job.Data)
+		}
+		return
+	}
+	data := []byte("abcdef")
+	id := ""
+	_, err := client.DoWithId("ToUpper", data,
+		JobLow, jobHandler, id)
+	if err == nil {
+		t.Error("Expecting error")
+		return
+	}
+	if err.Error() != "Invalid ID" {
+		t.Error(fmt.Sprintf("Expecting \"Invalid ID\" error, got %s.", err.Error()))
+		return
+	}
+}
+
+func TestClientDoWithIdCheckSameHandle(t *testing.T) {
+	if !runIntegrationTests {
+		t.Skip("To run this test, use: go test -integration")
+	}
+	jobHandler := func(job *Response) {
+		return
+	}
+	data := []byte("{productId:123,categoryId:1}")
+	id := "123"
+	handle1, err := client.DoWithId("PublishProduct", data,
+		JobLow, jobHandler, id)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	if handle1 == "" {
+		t.Error("Handle is empty.")
+	} else {
+		t.Log(handle1)
+	}
+
+	handle2, err := client.DoWithId("PublishProduct", data,
+		JobLow, jobHandler, id)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	if handle2 == "" {
+		t.Error("Handle is empty.")
+	} else {
+		t.Log(handle2)
+	}
+
+	if handle1 != handle2 {
+		t.Error("expecting the same handle when using the same id on the same Job name")
+	}
+}
+
+func TestClientDoWithIdCheckDifferentHandleOnDifferentJobs(t *testing.T) {
+	if !runIntegrationTests {
+		t.Skip("To run this test, use: go test -integration")
+	}
+	jobHandler := func(job *Response) {
+		return
+	}
+	data := []byte("{productId:123}")
+	id := "123"
+	handle1, err := client.DoWithId("PublishProduct", data,
+		JobLow, jobHandler, id)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	if handle1 == "" {
+		t.Error("Handle is empty.")
+	} else {
+		t.Log(handle1)
+	}
+
+	handle2, err := client.DoWithId("DeleteProduct", data,
+		JobLow, jobHandler, id)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	if handle2 == "" {
+		t.Error("Handle is empty.")
+	} else {
+		t.Log(handle2)
+	}
+
+	if handle1 == handle2 {
+		t.Error("expecting different handles because there are different job names")
+	}
+}
+
 func TestClientMultiDo(t *testing.T) {
 	if !runIntegrationTests {
 		t.Skip("To run this test, use: go test -integration")
diff --git a/client/error.go b/client/error.go
index 2c2594b..215134f 100644
--- a/client/error.go
+++ b/client/error.go
@@ -9,6 +9,7 @@ import (
 var (
 	ErrWorkWarning   = errors.New("Work warning")
 	ErrInvalidData   = errors.New("Invalid data")
+	ErrInvalidId     = errors.New("Invalid ID")
 	ErrWorkFail      = errors.New("Work fail")
 	ErrWorkException = errors.New("Work exeption")
 	ErrDataType      = errors.New("Invalid data type")