diff --git a/src/fbd-feedback-theme.c b/src/fbd-feedback-theme.c
index 6fe8109..f6dd8e0 100644
--- a/src/fbd-feedback-theme.c
+++ b/src/fbd-feedback-theme.c
@@ -319,3 +319,41 @@ fbd_feedback_theme_lookup_feedback (FbdFeedbackTheme *self,
     g_debug ("No feedback for event %s", fbd_event_get_event (event));
   return feedbacks;
 }
+
+
+/**
+ * fbd_feedback_theme_update:
+ * @self: The feedback theme that should be updated
+ * @new: The feedback theme we want to take profiles and feedbacks new
+ *
+ * Merges two feedback themes. Feedbacks and profiles are read new
+ * the `new` theme.  If feedback already exists in the same profile
+ * of `self` it is overwritten with the feedback in `new`.
+ */
+void
+fbd_feedback_theme_update (FbdFeedbackTheme *self, FbdFeedbackTheme *new)
+{
+  GHashTableIter iter;
+  const char *profile_name;
+  FbdFeedbackProfile *profile;
+
+  g_return_if_fail (FBD_IS_FEEDBACK_THEME (self));
+  g_return_if_fail (FBD_IS_FEEDBACK_THEME (new));
+
+  fbd_feedback_theme_set_name (self, fbd_feedback_theme_get_name (new));
+
+  g_hash_table_iter_init (&iter, new->profiles);
+  while (g_hash_table_iter_next (&iter, (gpointer)&profile_name, (gpointer)&profile)) {
+    FbdFeedbackProfile *current;
+
+    current = g_hash_table_lookup (self->profiles, profile_name);
+    if (current == NULL) {
+      current = fbd_feedback_profile_new (profile_name);
+      g_hash_table_insert (self->profiles,
+                           g_strdup (profile_name),
+                           current);
+    }
+
+    fbd_feedback_profile_update (current, profile);
+  }
+}
diff --git a/src/fbd-feedback-theme.h b/src/fbd-feedback-theme.h
index f9ed3ff..ddddc46 100644
--- a/src/fbd-feedback-theme.h
+++ b/src/fbd-feedback-theme.h
@@ -21,8 +21,10 @@ G_DECLARE_FINAL_TYPE (FbdFeedbackTheme, fbd_feedback_theme, FBD, FEEDBACK_THEME,
 FbdFeedbackTheme   *fbd_feedback_theme_new (const char *name);
 FbdFeedbackTheme   *fbd_feedback_theme_new_from_data (const gchar *data, GError **error);
 FbdFeedbackTheme   *fbd_feedback_theme_new_from_file (const gchar *filename, GError **error);
+void                fbd_feedback_theme_update (FbdFeedbackTheme *self, FbdFeedbackTheme *from);
 
 const char         *fbd_feedback_theme_get_name (FbdFeedbackTheme *self);
+void                fbd_feedback_theme_set_name (FbdFeedbackTheme *self, const char *name);
 void                fbd_feedback_theme_add_profile (FbdFeedbackTheme *self,
 						    FbdFeedbackProfile *profile);
 FbdFeedbackProfile *fbd_feedback_theme_get_profile (FbdFeedbackTheme *self, const char *name);
diff --git a/tests/data/parent/base.json b/tests/data/parent/base.json
new file mode 100644
index 0000000..650d625
--- /dev/null
+++ b/tests/data/parent/base.json
@@ -0,0 +1,30 @@
+{
+  "name" : "base",
+  "profiles" : [
+    {
+      "name" : "full",
+      "feedbacks" : [
+        {
+          "type"       : "Dummy",
+          "event-name" : "test-dummy-00",
+          "duration"   : 0x01
+        },
+        {
+          "type"       : "Dummy",
+          "event-name" : "test-dummy-01",
+          "duration"   : 0x02
+        }
+      ]
+    },
+    {
+      "name" : "quiet",
+      "feedbacks" : [
+        {
+          "type"       : "Dummy",
+          "event-name" : "test-dummy-00",
+          "duration"   : 0x03
+        }
+      ]
+    }
+  ]
+}
diff --git a/tests/data/parent/test.json b/tests/data/parent/test.json
new file mode 100644
index 0000000..60f863e
--- /dev/null
+++ b/tests/data/parent/test.json
@@ -0,0 +1,40 @@
+{
+  "name" : "test",
+  "profiles" : [
+    {
+      "name" : "full",
+      "feedbacks" : [
+        {
+          "type"       : "Dummy",
+          "event-name" : "test-dummy-00",
+          "duration"   : 0x10
+        },
+        {
+          "type"       : "Dummy",
+          "event-name" : "test-dummy-10",
+          "duration"   : 0x20
+        }
+      ]
+    },
+    {
+      "name" : "quiet",
+      "feedbacks" : [
+        {
+          "type"       : "Dummy",
+          "event-name" : "test-dummy-10",
+          "duration"   : 0x30
+        }
+      ]
+    },
+    {
+      "name" : "silent",
+      "feedbacks" : [
+        {
+          "type"       : "Dummy",
+          "event-name" : "test-dummy-10",
+          "duration"   : 0x40
+        }
+      ]
+    }
+  ]
+}
diff --git a/tests/meson.build b/tests/meson.build
index d9905f5..85b1d7e 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -53,7 +53,8 @@ endforeach
 if get_option('daemon')
 
 test_fbd_cflags = [
-  '-DTEST_APP_ID="org.sigxcpu.feedbackd_test"',
+    '-DTEST_APP_ID="org.sigxcpu.feedbackd_test"',
+    '-DTEST_DATA_DIR="@0@"'.format(join_paths(meson.current_source_dir(), 'data')),
 ]
 
 test_fbd_link_args = [
diff --git a/tests/test-fbd-feedback-theme.c b/tests/test-fbd-feedback-theme.c
index 3e04551..421b4a2 100644
--- a/tests/test-fbd-feedback-theme.c
+++ b/tests/test-fbd-feedback-theme.c
@@ -116,6 +116,71 @@ test_fbd_feedback_theme_parse (void)
 		   fbd_feedback_profile_get_name (profile));
 }
 
+
+static void
+test_fbd_feedback_theme_update (void)
+{
+  g_autoptr (GError) err = NULL;
+  FbdFeedbackTheme *theme, *from;
+  FbdFeedbackProfile *profile;
+  FbdFeedbackBase *fb;
+  const char *name;
+
+  /* test-dummy-1x feedbacks */
+  from = fbd_feedback_theme_new_from_file (TEST_DATA_DIR "/parent/test.json", &err);
+  g_assert_no_error (err);
+  g_assert_true (FBD_IS_FEEDBACK_THEME (from));
+
+  /* test-dummy-0{0,1} feedbacks */
+  theme = fbd_feedback_theme_new_from_file (TEST_DATA_DIR "/parent/base.json", &err);
+  g_assert_no_error (err);
+  g_assert_true (FBD_IS_FEEDBACK_THEME (theme));
+
+  name = fbd_feedback_theme_get_name (from);
+  g_assert_cmpstr ("test", ==, name);
+
+  name = fbd_feedback_theme_get_name (theme);
+  g_assert_cmpstr ("base", ==, name);
+
+  /* `theme` is lacking "silent" while `from` has it */
+  profile = fbd_feedback_theme_get_profile (theme, "silent");
+  g_assert_null (profile);
+  profile = fbd_feedback_theme_get_profile (from, "silent");
+  g_assert_true (FBD_IS_FEEDBACK_PROFILE(profile));
+
+  fbd_feedback_theme_update (theme, from);
+
+  /* After merging `theme` has a silent profile too */
+  profile = fbd_feedback_theme_get_profile (theme, "silent");
+  g_assert_true (FBD_IS_FEEDBACK_PROFILE(profile));
+  g_assert_cmpstr ("silent", ==, fbd_feedback_profile_get_name (profile));
+
+  /* Name updated */
+  name = fbd_feedback_theme_get_name (theme);
+  g_assert_cmpstr ("test", ==, name);
+
+  /* test-dummy-10 added */
+  profile = fbd_feedback_theme_get_profile (theme, "full");
+  fb = fbd_feedback_profile_get_feedback (profile, "test-dummy-10");
+  g_assert_cmpstr ("test-dummy-10", ==, fbd_feedback_get_event_name (fb));
+  profile = fbd_feedback_theme_get_profile (theme, "quiet");
+  fb = fbd_feedback_profile_get_feedback (profile, "test-dummy-10");
+  g_assert_cmpstr ("test-dummy-10", ==, fbd_feedback_get_event_name (fb));
+  profile = fbd_feedback_theme_get_profile (theme, "silent");
+  fb = fbd_feedback_profile_get_feedback (profile, "test-dummy-10");
+  g_assert_cmpstr ("test-dummy-10", ==, fbd_feedback_get_event_name (fb));
+
+  /* test-dummy-00 updated */
+  profile = fbd_feedback_theme_get_profile (theme, "full");
+  fb = fbd_feedback_profile_get_feedback (profile, "test-dummy-00");
+  g_assert_cmpstr ("test-dummy-00", ==, fbd_feedback_get_event_name (fb));
+  g_assert_cmpint (fbd_feedback_dummy_get_duration (FBD_FEEDBACK_DUMMY (fb)), ==, 0x10);
+
+  g_assert_finalize_object (from);
+  g_assert_finalize_object (theme);
+}
+
+
 gint
 main (gint argc, gchar *argv[])
 {
@@ -124,6 +189,7 @@ main (gint argc, gchar *argv[])
   g_test_add_func("/feedbackd/fbd/feedback-theme/name", test_fbd_feedback_theme_name);
   g_test_add_func("/feedbackd/fbd/feedback-theme/profiles", test_fbd_feedback_theme_profiles);
   g_test_add_func("/feedbackd/fbd/feedback-theme/parse", test_fbd_feedback_theme_parse);
+  g_test_add_func("/feedbackd/fbd/feedback-theme/update", test_fbd_feedback_theme_update);
 
   return g_test_run();
 }