diff --git a/charms/garm/src/garm_api.py b/charms/garm/src/garm_api.py
index d321864b..3f98ef49 100644
--- a/charms/garm/src/garm_api.py
+++ b/charms/garm/src/garm_api.py
@@ -14,6 +14,7 @@
 from garm_client.api.controller_info_api import ControllerInfoApi
 from garm_client.api.credentials_api import CredentialsApi
 from garm_client.api.first_run_api import FirstRunApi
+from garm_client.api.instances_api import InstancesApi
 from garm_client.api.login_api import LoginApi
 from garm_client.api.organizations_api import OrganizationsApi
 from garm_client.api.providers_api import ProvidersApi
@@ -29,6 +30,7 @@
 from garm_client.models.create_scale_set_params import CreateScaleSetParams
 from garm_client.models.create_template_params import CreateTemplateParams
 from garm_client.models.forge_credentials import ForgeCredentials
+from garm_client.models.instance import Instance
 from garm_client.models.new_user_params import NewUserParams
 from garm_client.models.organization import Organization
 from garm_client.models.password_login_params import PasswordLoginParams
@@ -529,6 +531,48 @@ def list_scalesets(self) -> list[ScaleSet]:
             except urllib3.exceptions.HTTPError as exc:
                 raise GarmConnectionError(f"GARM connection error: {exc}") from exc
 
+    def list_scale_set_instances(self, scaleset_id: int) -> list[Instance]:
+        """List runner instances belonging to a scaleset."""
+        with self._api_client() as client:
+            try:
+                return (
+                    InstancesApi(api_client=client).list_scale_set_instances(
+                        scaleset_id=str(scaleset_id),
+                        _request_timeout=_REQUEST_TIMEOUT,
+                    )
+                    or []
+                )
+            except ApiException as exc:
+                raise GarmApiError(
+                    f"Failed to list instances for scaleset {scaleset_id} "
+                    f"({exc.status}): {exc.body}"
+                ) from exc
+            except urllib3.exceptions.HTTPError as exc:
+                raise GarmConnectionError(f"GARM connection error: {exc}") from exc
+
+    def delete_instance(
+        self,
+        instance_name: str,
+        *,
+        force_remove: bool = False,
+        bypass_gh_unauthorized: bool = False,
+    ) -> None:
+        """Request deletion of a GARM runner instance."""
+        with self._api_client() as client:
+            try:
+                InstancesApi(api_client=client).delete_instance(
+                    instance_name=instance_name,
+                    force_remove=force_remove,
+                    bypass_gh_unauthorized=bypass_gh_unauthorized,
+                    _request_timeout=_REQUEST_TIMEOUT,
+                )
+            except ApiException as exc:
+                raise GarmApiError(
+                    f"Failed to delete runner {instance_name} ({exc.status}): {exc.body}"
+                ) from exc
+            except urllib3.exceptions.HTTPError as exc:
+                raise GarmConnectionError(f"GARM connection error: {exc}") from exc
+
     def find_org_id(self, org_name: str) -> str | None:
         """Find a GARM organization's UUID by name.
 
diff --git a/charms/garm/tests/unit/test_garm_api.py b/charms/garm/tests/unit/test_garm_api.py
index 09df38c2..f7086bc9 100644
--- a/charms/garm/tests/unit/test_garm_api.py
+++ b/charms/garm/tests/unit/test_garm_api.py
@@ -254,6 +254,46 @@ def test_list_scalesets(api_response, expected_names):
     assert [ss.name for ss in result] == expected_names
 
 
+def test_list_scale_set_instances_converts_id_to_string():
+    """
+    arrange: An authenticated client and a generated InstancesApi response.
+    act: List instances for scaleset ID 42.
+    assert: The wrapper converts the integer ID to the generated client's required string.
+    """
+    client = GarmAuthenticatedClient(BASE_URL, "token")
+    instance = Instance(name="runner-1", status="running", scale_set_id=42)
+    with _stub_api_client(client):
+        with patch("garm_api.InstancesApi") as MockApi:
+            MockApi.return_value.list_scale_set_instances.return_value = [instance]
+            result = client.list_scale_set_instances(42)
+
+    MockApi.return_value.list_scale_set_instances.assert_called_once_with(
+        scaleset_id="42", _request_timeout=30
+    )
+    assert result == [instance]
+
+
+def test_delete_instance_passes_force_and_bypass_flags():
+    """
+    arrange: An authenticated client and a generated InstancesApi stub.
+    act: Delete a runner with both cleanup flags enabled.
+    assert: The wrapper forwards the runner name, flags, and request timeout.
+    """
+    client = GarmAuthenticatedClient(BASE_URL, "token")
+    with _stub_api_client(client):
+        with patch("garm_api.InstancesApi") as MockApi:
+            client.delete_instance(
+                "runner-1", force_remove=True, bypass_gh_unauthorized=True
+            )
+
+    MockApi.return_value.delete_instance.assert_called_once_with(
+        instance_name="runner-1",
+        force_remove=True,
+        bypass_gh_unauthorized=True,
+        _request_timeout=30,
+    )
+
+
 @pytest.mark.parametrize(
     "target, registered, expected",
     [