diff --git a/temporal/api/cloud/cloudservice/v1/request_response.proto b/temporal/api/cloud/cloudservice/v1/request_response.proto
index 8b78a25..8757a3a 100644
--- a/temporal/api/cloud/cloudservice/v1/request_response.proto
+++ b/temporal/api/cloud/cloudservice/v1/request_response.proto
@@ -144,6 +144,8 @@ message GetNamespacesRequest {
     // Filter namespaces by their name.
     // Optional, defaults to empty.
     string name = 3;
+    // Optional, defaults to showing only namespaces the calling principal has permissions for
+    temporal.api.cloud.namespace.v1.NamespaceVisibility visibility = 4;
 }
 
 message GetNamespacesResponse {
diff --git a/temporal/api/cloud/identity/v1/message.proto b/temporal/api/cloud/identity/v1/message.proto
index 65adc2e..48f3b42 100644
--- a/temporal/api/cloud/identity/v1/message.proto
+++ b/temporal/api/cloud/identity/v1/message.proto
@@ -69,3 +69,4 @@ message User {
     // Will not be set if the user has never been modified.
     google.protobuf.Timestamp last_modified_time = 8;
 }
+
diff --git a/temporal/api/cloud/namespace/v1/message.proto b/temporal/api/cloud/namespace/v1/message.proto
index 4904c31..8195079 100644
--- a/temporal/api/cloud/namespace/v1/message.proto
+++ b/temporal/api/cloud/namespace/v1/message.proto
@@ -130,4 +130,19 @@ message Namespace {
     // The date and time when the namespace was last modified.
     // Will not be set if the namespace has never been modified.
     google.protobuf.Timestamp last_modified_time = 11;
+    // Indicates which principals in the account can see that the namespace exists and view its configuration
+    NamespaceVisibility visibility = 12;
 }
+
+// Indicates which principals in an account are able to see that the namespace exists and view its configuration.
+enum NamespaceVisibility {
+  // Unspecified defaults to NAMESPACE_VISIBILITY_PERMISSIONS_REQUIRED
+  NAMESPACE_VISIBILITY_LEVEL_UNSPECIFIED = 0;
+
+  // A principal must have some form of permissions to the namespace in order to be able to see that it exists and view its configuration
+  NAMESPACE_VISIBILITY_LEVEL_PERMISSIONS_REQUIRED = 1;
+
+  // Any principal can see the namespace exists and view its configuration. Note that the actual namespace data (e.g. Workflows) 
+  // still cannot be accessed by a principal without the appropriate namespace permissions attached to it.
+  NAMESPACE_VISIBILITY_LEVEL_ALL_DEVELOPERS = 2;
+}
\ No newline at end of file