diff --git a/pkg/apis/flagger/v1alpha3/types.go b/pkg/apis/flagger/v1alpha3/types.go
old mode 100755
new mode 100644
index 20a98cd2a..d8ce519b2
--- a/pkg/apis/flagger/v1alpha3/types.go
+++ b/pkg/apis/flagger/v1alpha3/types.go
@@ -111,6 +111,7 @@ type CanaryAnalysis struct {
 	Interval   string                           `json:"interval"`
 	Threshold  int                              `json:"threshold"`
 	MaxWeight  int                              `json:"maxWeight"`
+	Mirror     bool                             `json:"mirror,omitempty"`
 	StepWeight int                              `json:"stepWeight"`
 	Metrics    []CanaryMetric                   `json:"metrics"`
 	Webhooks   []CanaryWebhook                  `json:"webhooks,omitempty"`
diff --git a/pkg/controller/controller_test.go b/pkg/controller/controller_test.go
index df6a40460..a9199ac64 100644
--- a/pkg/controller/controller_test.go
+++ b/pkg/controller/controller_test.go
@@ -267,6 +267,12 @@ func newTestCanary() *v1alpha3.Canary {
 	return cd
 }
 
+func newTestCanaryMirror() *v1alpha3.Canary {
+	cd := newTestCanary()
+	cd.Spec.CanaryAnalysis.Mirror = true
+	return cd
+}
+
 func newTestCanaryAB() *v1alpha3.Canary {
 	cd := &v1alpha3.Canary{
 		TypeMeta: metav1.TypeMeta{APIVersion: v1alpha3.SchemeGroupVersion.String()},
diff --git a/pkg/controller/scheduler.go b/pkg/controller/scheduler.go
index 035e7aa4e..0cc0f9c95 100644
--- a/pkg/controller/scheduler.go
+++ b/pkg/controller/scheduler.go
@@ -302,8 +302,9 @@ func (c *Controller) advanceCanary(name string, namespace string, skipLivenessCh
 	}
 
 	// check if the canary success rate is above the threshold
-	// skip check if no traffic is routed to canary
-	if canaryWeight == 0 && cd.Status.Iterations == 0 {
+	// skip check if no traffic is routed or mirrored to canary
+	if canaryWeight == 0 && cd.Status.Iterations == 0 &&
+		(cd.Spec.CanaryAnalysis.Mirror == false || mirrored == false) {
 		c.recordEventInfof(cd, "Starting canary analysis for %s.%s", cd.Spec.TargetRef.Name, cd.Namespace)
 
 		// run pre-rollout web hooks
@@ -429,16 +430,34 @@ func (c *Controller) advanceCanary(name string, namespace string, skipLivenessCh
 	if cd.Spec.CanaryAnalysis.StepWeight > 0 {
 		// increase traffic weight
 		if canaryWeight < maxWeight {
-			primaryWeight -= cd.Spec.CanaryAnalysis.StepWeight
-			if primaryWeight < 0 {
-				primaryWeight = 0
-			}
-			canaryWeight += cd.Spec.CanaryAnalysis.StepWeight
-			if canaryWeight > 100 {
-				canaryWeight = 100
+			// If in "mirror" mode, do one step of mirroring before shifting traffic to canary.
+			// When mirroring, all requests go to primary and canary, but only responses from
+			// primary go back to the user.
+			if cd.Spec.CanaryAnalysis.Mirror && canaryWeight == 0 {
+				if mirrored == false {
+					mirrored = true
+					primaryWeight = 100
+					canaryWeight = 0
+				} else {
+					mirrored = false
+					primaryWeight = 100 - cd.Spec.CanaryAnalysis.StepWeight
+					canaryWeight = cd.Spec.CanaryAnalysis.StepWeight
+				}
+				c.logger.With("canary", fmt.Sprintf("%s.%s", name, namespace)).
+					Infof("Running mirror step %d/%d/%t", primaryWeight, canaryWeight, mirrored)
+			} else {
+
+				primaryWeight -= cd.Spec.CanaryAnalysis.StepWeight
+				if primaryWeight < 0 {
+					primaryWeight = 0
+				}
+				canaryWeight += cd.Spec.CanaryAnalysis.StepWeight
+				if canaryWeight > 100 {
+					canaryWeight = 100
+				}
 			}
 
-			if err := meshRouter.SetRoutes(cd, primaryWeight, canaryWeight); err != nil {
+			if err := meshRouter.SetRoutes(cd, primaryWeight, canaryWeight, mirrored); err != nil {
 				c.recordEventWarningf(cd, "%v", err)
 				return
 			}
diff --git a/pkg/controller/scheduler_test.go b/pkg/controller/scheduler_test.go
index fec2a96bf..604afae0e 100644
--- a/pkg/controller/scheduler_test.go
+++ b/pkg/controller/scheduler_test.go
@@ -319,6 +319,64 @@ func TestScheduler_Promotion(t *testing.T) {
 	}
 }
 
+func TestScheduler_Mirroring(t *testing.T) {
+	mocks := SetupMocks(newTestCanaryMirror())
+	// init
+	mocks.ctrl.advanceCanary("podinfo", "default", true)
+
+	// update
+	dep2 := newTestDeploymentV2()
+	_, err := mocks.kubeClient.AppsV1().Deployments("default").Update(dep2)
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+
+	// detect pod spec changes
+	mocks.ctrl.advanceCanary("podinfo", "default", true)
+
+	// advance
+	mocks.ctrl.advanceCanary("podinfo", "default", true)
+
+	// check if traffic is mirrored to canary
+	primaryWeight, canaryWeight, mirrored, err := mocks.router.GetRoutes(mocks.canary)
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+
+	if primaryWeight != 100 {
+		t.Errorf("Got primary route %v wanted %v", primaryWeight, 100)
+	}
+
+	if canaryWeight != 0 {
+		t.Errorf("Got canary route %v wanted %v", canaryWeight, 0)
+	}
+
+	if mirrored != true {
+		t.Errorf("Got mirrored %v wanted %v", mirrored, true)
+	}
+
+	// advance
+	mocks.ctrl.advanceCanary("podinfo", "default", true)
+
+	// check if traffic is mirrored to canary
+	primaryWeight, canaryWeight, mirrored, err = mocks.router.GetRoutes(mocks.canary)
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+
+	if primaryWeight != 90 {
+		t.Errorf("Got primary route %v wanted %v", primaryWeight, 90)
+	}
+
+	if canaryWeight != 10 {
+		t.Errorf("Got canary route %v wanted %v", canaryWeight, 10)
+	}
+
+	if mirrored != false {
+		t.Errorf("Got mirrored %v wanted %v", mirrored, false)
+	}
+}
+
 func TestScheduler_ABTesting(t *testing.T) {
 	mocks := SetupMocks(newTestCanaryAB())
 	// init