diff --git a/pkg/kn/commands/service.go b/pkg/kn/commands/service.go
index 1f0802c93..77441e92a 100644
--- a/pkg/kn/commands/service.go
+++ b/pkg/kn/commands/service.go
@@ -27,5 +27,6 @@ func NewServiceCommand(p *KnParams) *cobra.Command {
 	serviceCmd.AddCommand(NewServiceDescribeCommand(p))
 	serviceCmd.AddCommand(NewServiceCreateCommand(p))
 	serviceCmd.AddCommand(NewServiceDeleteCommand(p))
+	serviceCmd.AddCommand(NewServiceUpdateCommand(p))
 	return serviceCmd
 }
diff --git a/pkg/kn/commands/service_update.go b/pkg/kn/commands/service_update.go
new file mode 100644
index 000000000..e302ac617
--- /dev/null
+++ b/pkg/kn/commands/service_update.go
@@ -0,0 +1,71 @@
+// Copyright © 2019 The Knative Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package commands
+
+import (
+	"errors"
+
+	serving_lib "github.com/knative/client/pkg/serving"
+	"github.com/spf13/cobra"
+	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func NewServiceUpdateCommand(p *KnParams) *cobra.Command {
+	var editFlags ConfigurationEditFlags
+
+	serviceUpdateCommand := &cobra.Command{
+		Use:   "update NAME",
+		Short: "Update a service.",
+		RunE: func(cmd *cobra.Command, args []string) (err error) {
+			if len(args) != 1 {
+				return errors.New("requires the service name.")
+			}
+
+			namespace, err := GetNamespace(cmd)
+			if err != nil {
+				return err
+			}
+
+			client, err := p.ServingFactory()
+			if err != nil {
+				return err
+			}
+
+			service, err := client.Services(namespace).Get(args[0], v1.GetOptions{})
+			if err != nil {
+				return err
+			}
+
+			config, err := serving_lib.GetConfiguration(service)
+			if err != nil {
+				return err
+			}
+			err = editFlags.Apply(config)
+			if err != nil {
+				return err
+			}
+
+			_, err = client.Services(namespace).Update(service)
+			if err != nil {
+				return err
+			}
+
+			return nil
+		},
+	}
+	AddNamespaceFlags(serviceUpdateCommand.Flags(), false)
+	editFlags.AddFlags(serviceUpdateCommand)
+	return serviceUpdateCommand
+}
diff --git a/pkg/kn/commands/service_update_test.go b/pkg/kn/commands/service_update_test.go
new file mode 100644
index 000000000..71c3dd9dd
--- /dev/null
+++ b/pkg/kn/commands/service_update_test.go
@@ -0,0 +1,109 @@
+// Copyright © 2019 The Knative Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package commands
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"testing"
+
+	servinglib "github.com/knative/client/pkg/serving"
+
+	"github.com/knative/serving/pkg/apis/serving/v1alpha1"
+	serving "github.com/knative/serving/pkg/client/clientset/versioned/typed/serving/v1alpha1"
+	"github.com/knative/serving/pkg/client/clientset/versioned/typed/serving/v1alpha1/fake"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	client_testing "k8s.io/client-go/testing"
+)
+
+func fakeServiceUpdate(original *v1alpha1.Service, args []string) (
+	action client_testing.Action,
+	updated *v1alpha1.Service,
+	output string,
+	err error) {
+
+	buf := new(bytes.Buffer)
+	fakeServing := &fake.FakeServingV1alpha1{&client_testing.Fake{}}
+	cmd := NewKnCommand(KnParams{
+		Output:         buf,
+		ServingFactory: func() (serving.ServingV1alpha1Interface, error) { return fakeServing, nil },
+	})
+	fakeServing.AddReactor("update", "*",
+		func(a client_testing.Action) (bool, runtime.Object, error) {
+			updateAction, ok := a.(client_testing.UpdateAction)
+			action = updateAction
+			if !ok {
+				return true, nil, fmt.Errorf("wrong kind of action %v", action)
+			}
+			updated, ok = updateAction.GetObject().(*v1alpha1.Service)
+			if !ok {
+				return true, nil, errors.New("was passed the wrong object")
+			}
+			return true, updated, nil
+		})
+	fakeServing.AddReactor("get", "*",
+		func(a client_testing.Action) (bool, runtime.Object, error) {
+			return true, original, nil
+		})
+	cmd.SetArgs(args)
+	err = cmd.Execute()
+	if err != nil {
+		return
+	}
+	output = buf.String()
+	return
+}
+
+func TestServiceUpdateImage(t *testing.T) {
+
+	orig := &v1alpha1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "knative.dev/v1alpha1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "foo",
+			Namespace: "default",
+		},
+		Spec: v1alpha1.ServiceSpec{
+			RunLatest: &v1alpha1.RunLatestType{},
+		},
+	}
+
+	config, err := servinglib.GetConfiguration(orig)
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	servinglib.UpdateImage(config, "gcr.io/foo/bar:baz")
+
+	action, updated, _, err := fakeServiceUpdate(orig, []string{
+		"service", "update", "foo", "--image", "gcr.io/foo/quux:xyzzy"})
+
+	if err != nil {
+		t.Fatal(err)
+	} else if !action.Matches("update", "services") {
+		t.Fatalf("Bad action %v", action)
+	}
+	conf, err := servinglib.GetConfiguration(updated)
+	if err != nil {
+		t.Fatal(err)
+	} else if conf.RevisionTemplate.Spec.Container.Image != "gcr.io/foo/quux:xyzzy" {
+		t.Fatalf("wrong image set: %v", conf.RevisionTemplate.Spec.Container.Image)
+	}
+}