diff --git a/on_modify.py b/on_modify.py
index 1fcafc0..b8663fd 100755
--- a/on_modify.py
+++ b/on_modify.py
@@ -51,7 +51,13 @@ def extract_tags_from(json_obj):
         tags.append(json_obj['project'])
 
     if 'tags' in json_obj:
-        tags.extend(json_obj['tags'])
+        if type(json_obj['tags']) is str:
+            # Usage of tasklib (e.g. in taskpirate) converts the tag list into a string
+            # If this is the case, convert it back into a list first
+            # See https://github.com/tbabej/taskpirate/issues/11
+            tags.extend(json_obj['tags'].split(','))
+        else:
+            tags.extend(json_obj['tags'])
 
     return tags
 
diff --git a/test/test_on-modify_unit.py b/test/test_on-modify_unit.py
index 99f9bea..a191211 100755
--- a/test/test_on-modify_unit.py
+++ b/test/test_on-modify_unit.py
@@ -367,3 +367,62 @@ def test_hook_should_process_stop():
     )
 
     verify(subprocess).call(['timew', 'stop', 'Foo', ':yes'])
+
+@pytest.mark.usefixtures("teardown")
+def test_hook_should_process_start_issue34_with_multiple_tags():
+    """on-modify hook should process 'task start' (issue #34) with multiple tags"""
+
+    when(subprocess).call(...)
+    on_modify.main(
+        json.loads(
+            '''{
+            "description": "Foo",
+            "entry": "20190820T203842Z",
+            "modified": "20190820T203842Z",
+            "status": "pending",
+            "tags": ["abc", "xyz"],
+            "uuid": "16af44c5-57d2-43bf-97ed-cf2e541d927f"
+            }'''),
+        json.loads(
+            '''{
+            "description": "Foo",
+            "entry": "20190820T203842Z",
+            "modified": "20190820T203842Z",
+            "start": "20190820T203842Z",
+            "status": "pending",
+            "tags": "abc,xyz",
+            "uuid": "16af44c5-57d2-43bf-97ed-cf2e541d927f"
+            }''')
+    )
+
+    verify(subprocess).call(['timew', 'start', 'Foo', 'abc', 'xyz', ':yes'])
+
+
+@pytest.mark.usefixtures("teardown")
+def test_hook_should_process_start_issue34_with_single_tags():
+    """on-modify hook should process 'task start' (issue #34) with single tags"""
+
+    when(subprocess).call(...)
+    on_modify.main(
+        json.loads(
+            '''{
+            "description": "Foo",
+            "entry": "20190820T203842Z",
+            "modified": "20190820T203842Z",
+            "status": "pending",
+            "tags": ["abc"],
+            "uuid": "16af44c5-57d2-43bf-97ed-cf2e541d927f"
+            }'''),
+        json.loads(
+            '''{
+            "description": "Foo",
+            "entry": "20190820T203842Z",
+            "modified": "20190820T203842Z",
+            "start": "20190820T203842Z",
+            "status": "pending",
+            "tags": "abc",
+            "uuid": "16af44c5-57d2-43bf-97ed-cf2e541d927f"
+            }''')
+    )
+
+    verify(subprocess).call(['timew', 'start', 'Foo', 'abc', ':yes'])