diff --git a/setup.cfg b/setup.cfg
index 60a81b4..8474f40 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,6 +1,6 @@
 [metadata]
 name = asyncio-taskpool
-version = 0.5.0
+version = 0.5.1
 author = Daniil Fajnberg
 author_email = mail@daniil.fajnberg.de
 description = Dynamically manage pools of asyncio tasks
diff --git a/src/asyncio_taskpool/pool.py b/src/asyncio_taskpool/pool.py
index 9f0abfc..183cbc7 100644
--- a/src/asyncio_taskpool/pool.py
+++ b/src/asyncio_taskpool/pool.py
@@ -178,23 +178,26 @@ class BaseTaskPool:
         """
         return self._enough_room.locked()
 
-    def get_task_group_ids(self, group_name: str) -> Set[int]:
+    def get_group_ids(self, *group_names: str) -> Set[int]:
         """
-        Returns the set of IDs of all tasks in the specified group.
+        Returns the set of IDs of all tasks in the specified groups.
 
         Args:
-            group_name: Must be a name of a task group that exists within the pool.
+            *group_names: Each element must be a name of a task group that exists within the pool.
 
         Returns:
-            Set of integers representing the task IDs belonging to the specified group.
+            Set of integers representing the task IDs belonging to the specified groups.
 
         Raises:
-            `InvalidGroupName` if no task group named `group_name` exists in the pool.
+            `InvalidGroupName` if one of the specified `group_names` does not exist in the pool.
         """
-        try:
-            return set(self._task_groups[group_name])
-        except KeyError:
-            raise exceptions.InvalidGroupName(f"No task group named {group_name} exists in this pool.")
+        ids = set()
+        for name in group_names:
+            try:
+                ids.update(self._task_groups[name])
+            except KeyError:
+                raise exceptions.InvalidGroupName(f"No task group named {name} exists in this pool.")
+        return ids
 
     def _check_start(self, *, awaitable: Awaitable = None, function: CoroutineFunc = None,
                      ignore_lock: bool = False) -> None:
diff --git a/tests/test_pool.py b/tests/test_pool.py
index aef5fc0..e467d57 100644
--- a/tests/test_pool.py
+++ b/tests/test_pool.py
@@ -163,12 +163,12 @@ class BaseTaskPoolTestCase(CommonTestCase):
     def test_is_full(self):
         self.assertEqual(self.task_pool._enough_room.locked(), self.task_pool.is_full)
 
-    def test_get_task_group_ids(self):
+    def test_get_group_ids(self):
         group_name, ids = 'abcdef', [1, 2, 3]
         self.task_pool._task_groups[group_name] = MagicMock(__iter__=lambda _: iter(ids))
-        self.assertEqual(set(ids), self.task_pool.get_task_group_ids(group_name))
+        self.assertEqual(set(ids), self.task_pool.get_group_ids(group_name))
         with self.assertRaises(exceptions.InvalidGroupName):
-            self.task_pool.get_task_group_ids('something else')
+            self.task_pool.get_group_ids(group_name, 'something else')
 
     async def test__check_start(self):
         self.task_pool._closed = True