diff --git a/apis/cloudbuild/v1alpha1/conversion.go b/apis/cloudbuild/v1alpha1/conversion.go
index 768b96cbb3..11bc325119 100644
--- a/apis/cloudbuild/v1alpha1/conversion.go
+++ b/apis/cloudbuild/v1alpha1/conversion.go
@@ -25,6 +25,8 @@ func Convert_WorkerPool_API_v1_To_KRM_status(in *cloudbuildpb.WorkerPool, out *C
 		return nil
 	}
 	out.ObservedState = &CloudBuildWorkerPoolObservedState{}
+
+	out.ObservedState.ETag = &in.Etag
 	if err := Convert_PrivatePoolV1Config_API_v1_To_KRM(in.GetPrivatePoolV1Config(), out.ObservedState); err != nil {
 		return err
 	}
diff --git a/apis/cloudbuild/v1alpha1/workerpool_types.go b/apis/cloudbuild/v1alpha1/workerpool_types.go
index 6397bfdf3a..b2fabdce91 100644
--- a/apis/cloudbuild/v1alpha1/workerpool_types.go
+++ b/apis/cloudbuild/v1alpha1/workerpool_types.go
@@ -86,6 +86,10 @@ type CloudBuildWorkerPoolObservedState struct {
 	// +optional
 	WorkerConfig  *WorkerConfig       `json:"workerConfig,omitempty"`
 	NetworkConfig *NetworkConfigState `json:"networkConfig,omitempty"`
+
+	/* The Checksum computed by the server, using weak indicator.*/
+	// +optional
+	ETag *string `json:"etag,omitempty"`
 }
 
 type NetworkConfigState struct {
diff --git a/apis/cloudbuild/v1alpha1/zz_generated.deepcopy.go b/apis/cloudbuild/v1alpha1/zz_generated.deepcopy.go
index 2e9aed9c88..e4bbc1fbe6 100644
--- a/apis/cloudbuild/v1alpha1/zz_generated.deepcopy.go
+++ b/apis/cloudbuild/v1alpha1/zz_generated.deepcopy.go
@@ -92,6 +92,11 @@ func (in *CloudBuildWorkerPoolObservedState) DeepCopyInto(out *CloudBuildWorkerP
 		*out = new(NetworkConfigState)
 		**out = **in
 	}
+	if in.ETag != nil {
+		in, out := &in.ETag, &out.ETag
+		*out = new(string)
+		**out = **in
+	}
 }
 
 // DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new CloudBuildWorkerPoolObservedState.
diff --git a/config/crds/resources/apiextensions.k8s.io_v1_customresourcedefinition_cloudbuildworkerpools.cloudbuild.cnrm.cloud.google.com.yaml b/config/crds/resources/apiextensions.k8s.io_v1_customresourcedefinition_cloudbuildworkerpools.cloudbuild.cnrm.cloud.google.com.yaml
index f072f3b0bb..6581240c36 100644
--- a/config/crds/resources/apiextensions.k8s.io_v1_customresourcedefinition_cloudbuildworkerpools.cloudbuild.cnrm.cloud.google.com.yaml
+++ b/config/crds/resources/apiextensions.k8s.io_v1_customresourcedefinition_cloudbuildworkerpools.cloudbuild.cnrm.cloud.google.com.yaml
@@ -180,6 +180,9 @@ spec:
                     description: The creation timestamp of the workerpool.
                     format: date-time
                     type: string
+                  etag:
+                    description: The Checksum computed by the server, using weak indicator.
+                    type: string
                   networkConfig:
                     properties:
                       egressOption:
diff --git a/mockgcp/common/fields/etag.go b/mockgcp/common/fields/etag.go
new file mode 100644
index 0000000000..8f90639c1e
--- /dev/null
+++ b/mockgcp/common/fields/etag.go
@@ -0,0 +1,71 @@
+// Copyright 2024 Google LLC
+//
+// 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 fields
+
+import (
+	"crypto/sha256"
+	"encoding/base64"
+	"fmt"
+
+	"google.golang.org/protobuf/encoding/prototext"
+	"google.golang.org/protobuf/proto"
+)
+
+var mustFields = []string{
+	"displayName",
+	"state",
+}
+
+// ComputeEtag computes the etag of the proto object with weak indicator.
+func ComputeEtag(obj proto.Message) string {
+	pb := proto.Clone(obj)
+
+	// ignore dynamic fields like timestampe or uniqueId.
+	descriptor := pb.ProtoReflect().Descriptor()
+	fieldDescs := descriptor.Fields()
+	for i := 0; i < fieldDescs.Len(); i++ {
+		fieldDesc := fieldDescs.Get(i)
+		must := false
+		for _, mustField := range mustFields {
+			if fieldDesc.JSONName() == mustField {
+				must = true
+			}
+		}
+		if !must {
+			pb.ProtoReflect().Clear(fieldDesc)
+		}
+	}
+
+	m, err := prototext.Marshal(pb)
+	if err != nil {
+		panic(fmt.Sprintf("converting to prototext: %v", err))
+	}
+	h := sha256.Sum256([]byte(m))
+	str := base64.StdEncoding.EncodeToString(h[:])
+	strong := fmt.Sprintf(`"%s"`, str) // ETag must be quoted.
+	return "W/" + strong
+}
+
+func ComputeEtagBytes(obj proto.Message) []byte {
+	return []byte(ComputeEtag(obj))
+}
+
+func ComputeEtagPtr(obj proto.Message) *string {
+	return ptrTo(ComputeEtag(obj))
+}
+
+func ptrTo[T any](t T) *T {
+	return &t
+}
diff --git a/mockgcp/mockcloudbuild/workerpool.go b/mockgcp/mockcloudbuild/workerpool.go
index 393a1c9fda..674e2950da 100644
--- a/mockgcp/mockcloudbuild/workerpool.go
+++ b/mockgcp/mockcloudbuild/workerpool.go
@@ -20,6 +20,7 @@ import (
 	"strings"
 
 	"cloud.google.com/go/longrunning/autogen/longrunningpb"
+	"github.com/GoogleCloudPlatform/k8s-config-connector/mockgcp/common/fields"
 	"github.com/GoogleCloudPlatform/k8s-config-connector/mockgcp/common/projects"
 	pb "github.com/GoogleCloudPlatform/k8s-config-connector/mockgcp/generated/mockgcp/devtools/cloudbuild/v1"
 	"google.golang.org/grpc/codes"
@@ -77,6 +78,7 @@ func (s *CloudBuildV1) CreateWorkerPool(ctx context.Context, req *pb.CreateWorke
 		result.CreateTime = now
 		result.UpdateTime = now
 		result.State = pb.WorkerPool_RUNNING
+		result.Etag = fields.ComputeEtag(result)
 		return result, nil
 	})
 }
@@ -99,7 +101,7 @@ func (s *CloudBuildV1) UpdateWorkerPool(ctx context.Context, req *pb.UpdateWorke
 		f := target.FieldByName(path)
 		if f.IsValid() && f.CanSet() {
 			switch f.Kind() {
-			case reflect.Int:
+			case reflect.Int, reflect.Int64:
 				intVal := source.FieldByName(path).Int()
 				f.SetInt(intVal)
 			case reflect.String:
@@ -122,6 +124,7 @@ func (s *CloudBuildV1) UpdateWorkerPool(ctx context.Context, req *pb.UpdateWorke
 		result := proto.Clone(obj).(*pb.WorkerPool)
 		result.UpdateTime = now
 		result.State = pb.WorkerPool_RUNNING
+		result.Etag = fields.ComputeEtag(result)
 		return result, nil
 	})
 }
diff --git a/pkg/clients/generated/apis/cloudbuild/v1alpha1/cloudbuildworkerpool_types.go b/pkg/clients/generated/apis/cloudbuild/v1alpha1/cloudbuildworkerpool_types.go
index 73d62f9f33..38bfd72fb3 100644
--- a/pkg/clients/generated/apis/cloudbuild/v1alpha1/cloudbuildworkerpool_types.go
+++ b/pkg/clients/generated/apis/cloudbuild/v1alpha1/cloudbuildworkerpool_types.go
@@ -94,6 +94,10 @@ type WorkerpoolObservedStateStatus struct {
 	// +optional
 	CreateTime *string `json:"createTime,omitempty"`
 
+	/* The Checksum computed by the server, using weak indicator. */
+	// +optional
+	Etag *string `json:"etag,omitempty"`
+
 	// +optional
 	NetworkConfig *WorkerpoolNetworkConfigStatus `json:"networkConfig,omitempty"`
 
diff --git a/pkg/clients/generated/apis/cloudbuild/v1alpha1/zz_generated.deepcopy.go b/pkg/clients/generated/apis/cloudbuild/v1alpha1/zz_generated.deepcopy.go
index 12492f78c1..8eaf16910c 100644
--- a/pkg/clients/generated/apis/cloudbuild/v1alpha1/zz_generated.deepcopy.go
+++ b/pkg/clients/generated/apis/cloudbuild/v1alpha1/zz_generated.deepcopy.go
@@ -220,6 +220,11 @@ func (in *WorkerpoolObservedStateStatus) DeepCopyInto(out *WorkerpoolObservedSta
 		*out = new(string)
 		**out = **in
 	}
+	if in.Etag != nil {
+		in, out := &in.Etag, &out.Etag
+		*out = new(string)
+		**out = **in
+	}
 	if in.NetworkConfig != nil {
 		in, out := &in.NetworkConfig, &out.NetworkConfig
 		*out = new(WorkerpoolNetworkConfigStatus)
diff --git a/pkg/controller/direct/cloudbuild/workerpool_controller.go b/pkg/controller/direct/cloudbuild/workerpool_controller.go
index 41e998dace..760b76eca3 100644
--- a/pkg/controller/direct/cloudbuild/workerpool_controller.go
+++ b/pkg/controller/direct/cloudbuild/workerpool_controller.go
@@ -259,6 +259,7 @@ func (a *Adapter) Update(ctx context.Context, u *unstructured.Unstructured) erro
 
 	wp := &cloudbuildpb.WorkerPool{
 		Name: a.fullyQualifiedName(),
+		Etag: a.actual.Etag,
 	}
 	desired := a.desired.DeepCopy()
 	err := krm.Convert_WorkerPool_KRM_To_API_v1(desired, wp)
diff --git a/pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_generated_object_cloudbuildworkerpool.golden.yaml b/pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_generated_object_cloudbuildworkerpool.golden.yaml
index 3acbb4ad51..88dcb35386 100644
--- a/pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_generated_object_cloudbuildworkerpool.golden.yaml
+++ b/pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_generated_object_cloudbuildworkerpool.golden.yaml
@@ -33,6 +33,7 @@ status:
   observedGeneration: 2
   observedState:
     createTime: "1970-01-01T00:00:00Z"
+    etag: W/"pwzCjvRptOAz64ZilGUmgNZjYVh0LzD3Oh+zEbMPULw="
     networkConfig:
       egressOption: NO_PUBLIC_EGRESS
       peeredNetwork: projects/${projectId}/global/networks/computenetwork-${uniqueId}
diff --git a/pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_http.log b/pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_http.log
index d38bcce2cf..69b98084c3 100644
--- a/pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_http.log
+++ b/pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_http.log
@@ -593,6 +593,7 @@ X-Xss-Protection: 0
     "@type": "type.googleapis.com/google.devtools.cloudbuild.v1.WorkerPool",
     "createTime": "2024-04-01T12:34:56.123456Z",
     "displayName": "New CloudBuild WorkerPool",
+    "etag": "abcdef0123A=",
     "name": "projects/${projectId}/locations/us-central1/workerPools/cloudbuildworkerpool-${uniqueId}",
     "privatePoolV1Config": {
       "networkConfig": {
@@ -715,6 +716,7 @@ X-Xss-Protection: 0
   "response": {
     "@type": "type.googleapis.com/google.devtools.cloudbuild.v1.WorkerPool",
     "displayName": "New CloudBuild WorkerPool",
+    "etag": "abcdef0123A=",
     "name": "projects/${projectId}/locations/us-central1/workerPools/cloudbuildworkerpool-${uniqueId}",
     "privatePoolV1Config": {
       "networkConfig": {