diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 1076de5..6ece139 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,6 +1,9 @@
 Development version
 ===================
 
+ - sessionmanager.wait_for_tasks now wait for tasks that are started from
+   other tasks callbacks from different sessions.
+
 0.1.3 / 2015-06-16
 ==================
 
diff --git a/rcontrol/core.py b/rcontrol/core.py
index c356efc..0ef6f2a 100644
--- a/rcontrol/core.py
+++ b/rcontrol/core.py
@@ -361,11 +361,28 @@ def __delattr__(self, name):
     def wait_for_tasks(self, raise_if_error=True):
         """
         Wait for the running tasks lauched from the sessions.
+
+        Note that it also wait for tasks that are started from other tasks
+        callbacks, like on_finished.
+
+        :param raise_if_error: if True, raise all possible encountered
+            errors using :class:`TaskErrors`. Else the errors are returned
+            as a list.
         """
         errors = []
-        for session in self.values():
-            errs = session.wait_for_tasks(raise_if_error=False)
-            errors.extend(errs)
+        tasks_seen = TaskCache()
+        while True:
+            for session in self.values():
+                errs = session.wait_for_tasks(raise_if_error=False)
+                errors.extend(errs)
+            # look for tasks created after the wait (in callbacks of
+            # tasks from different sessions)
+            tasks = []
+            for session in self.values():
+                tasks.extend(session.tasks())
+            # if none, then just break - else loop to wait for them
+            if not any(t for t in tasks if t not in tasks_seen):
+                break
         if raise_if_error and errors:
             raise TaskErrors(errors)
         return errors
diff --git a/tests/test_core.py b/tests/test_core.py
index d58cd4f..355fd09 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -223,9 +223,13 @@ def test_that_only_sessions_can_be_stored_in_dict(self):
 
     def test_wait_for_tasks(self):
         self.sessions.s1 = create_session(
-            wait_for_tasks=Mock(return_value=[]))
+            wait_for_tasks=Mock(return_value=[]),
+            tasks=Mock(return_value=[]),
+        )
         self.sessions.s2 = create_session(
-            wait_for_tasks=Mock(return_value=[]))
+            wait_for_tasks=Mock(return_value=[]),
+            tasks=Mock(return_value=[]),
+        )
 
         self.assertEqual(self.sessions.wait_for_tasks(), [])
         self.sessions.s1.wait_for_tasks.assert_called_with(
@@ -236,9 +240,13 @@ def test_wait_for_tasks(self):
     def test_wait_for_tasks_with_tasks_errors(self):
         exc1, exc2 = Exception(), Exception()
         self.sessions.s1 = create_session(
-            wait_for_tasks=Mock(return_value=[exc1]))
+            wait_for_tasks=Mock(return_value=[exc1]),
+            tasks=Mock(return_value=[]),
+        )
         self.sessions.s2 = create_session(
-            wait_for_tasks=Mock(return_value=[exc2]))
+            wait_for_tasks=Mock(return_value=[exc2]),
+            tasks=Mock(return_value=[]),
+        )
 
         # by default, this raise an exception
         with self.assertRaises(core.TaskErrors) as cm:
@@ -278,6 +286,7 @@ def test_inside_with_with_task_errors(self):
                 s.s1 = create_session(
                     wait_for_tasks=Mock(return_value=[exc1]),
                     auto_close=True,
+                    tasks=Mock(return_value=[]),
                 )
 
     def test_inside_with_with_errors(self):
@@ -289,6 +298,7 @@ def test_inside_with_with_errors(self):
                 s.s1 = create_session(
                     wait_for_tasks=Mock(return_value=[exc1]),
                     auto_close=True,
+                    tasks=Mock(return_value=[]),
                 )
                 raise KeyboardInterrupt