diff --git a/doc/source/command-objects/project.rst b/doc/source/command-objects/project.rst
index ba741d1dc1..0be4e80680 100644
--- a/doc/source/command-objects/project.rst
+++ b/doc/source/command-objects/project.rst
@@ -58,6 +58,12 @@ Delete an existing project
     os project delete
         <project>
 
+.. option:: --domain <domain>
+
+    Domain owning :ref:`\<project\> <_project_delete-project>` (name or ID)
+
+    .. versionadded:: 3
+
 .. _project_delete-project:
 .. describe:: <project>
 
diff --git a/doc/source/command-objects/user.rst b/doc/source/command-objects/user.rst
index 53becf2799..24a2725b7d 100644
--- a/doc/source/command-objects/user.rst
+++ b/doc/source/command-objects/user.rst
@@ -80,6 +80,14 @@ Delete user
     os user delete
         <user>
 
+.. option:: --domain <domain>
+
+    Domain owning :ref:`\<user\> <_user_delete-user>` (name or ID)
+
+    .. versionadded:: 3
+
+.. _user_delete-user:
+
 .. describe:: <user>
 
     User to delete (name or ID)
diff --git a/openstackclient/identity/v3/group.py b/openstackclient/identity/v3/group.py
index 14838bba57..5d3cf6422a 100644
--- a/openstackclient/identity/v3/group.py
+++ b/openstackclient/identity/v3/group.py
@@ -169,12 +169,26 @@ class DeleteGroup(command.Command):
             'group',
             metavar='<group>',
             help='Name or ID of group to delete')
+        parser.add_argument(
+            '--domain',
+            metavar='<domain>',
+            help='Domain where group resides (name or ID)',
+        )
         return parser
 
     def take_action(self, parsed_args):
         self.log.debug('take_action(%s)', parsed_args)
         identity_client = self.app.client_manager.identity
-        group = utils.find_resource(identity_client.groups, parsed_args.group)
+
+        if parsed_args.domain:
+            domain = common.find_domain(identity_client, parsed_args.domain)
+            group = utils.find_resource(identity_client.groups,
+                                        parsed_args.group,
+                                        domain_id=domain.id)
+        else:
+            group = utils.find_resource(identity_client.groups,
+                                        parsed_args.group)
+
         identity_client.groups.delete(group.id)
         return
 
diff --git a/openstackclient/identity/v3/project.py b/openstackclient/identity/v3/project.py
index 3b0e92fd8c..1e3977ba36 100644
--- a/openstackclient/identity/v3/project.py
+++ b/openstackclient/identity/v3/project.py
@@ -126,16 +126,25 @@ class DeleteProject(command.Command):
             metavar='<project>',
             help='Project to delete (name or ID)',
         )
+        parser.add_argument(
+            '--domain',
+            metavar='<domain>',
+            help='Domain owning <project> (name or ID)',
+        )
         return parser
 
     def take_action(self, parsed_args):
         self.log.debug('take_action(%s)', parsed_args)
         identity_client = self.app.client_manager.identity
 
-        project = utils.find_resource(
-            identity_client.projects,
-            parsed_args.project,
-        )
+        if parsed_args.domain:
+            domain = common.find_domain(identity_client, parsed_args.domain)
+            project = utils.find_resource(identity_client.projects,
+                                          parsed_args.project,
+                                          domain_id=domain.id)
+        else:
+            project = utils.find_resource(identity_client.projects,
+                                          parsed_args.project)
 
         identity_client.projects.delete(project.id)
         return
diff --git a/openstackclient/identity/v3/user.py b/openstackclient/identity/v3/user.py
index 10ffce36b8..665dd4bb16 100644
--- a/openstackclient/identity/v3/user.py
+++ b/openstackclient/identity/v3/user.py
@@ -148,16 +148,25 @@ class DeleteUser(command.Command):
             metavar='<user>',
             help='User to delete (name or ID)',
         )
+        parser.add_argument(
+            '--domain',
+            metavar='<domain>',
+            help='Domain owning <user> (name or ID)',
+        )
         return parser
 
     def take_action(self, parsed_args):
         self.log.debug('take_action(%s)', parsed_args)
         identity_client = self.app.client_manager.identity
 
-        user = utils.find_resource(
-            identity_client.users,
-            parsed_args.user,
-        )
+        if parsed_args.domain:
+            domain = common.find_domain(identity_client, parsed_args.domain)
+            user = utils.find_resource(identity_client.users,
+                                       parsed_args.user,
+                                       domain_id=domain.id)
+        else:
+            user = utils.find_resource(identity_client.users,
+                                       parsed_args.user)
 
         identity_client.users.delete(user.id)
         return