diff --git a/qapi-schema-test.json b/qapi-schema-test.json
index 2b38919..8c7f9f7 100644
--- a/qapi-schema-test.json
+++ b/qapi-schema-test.json
@@ -22,6 +22,16 @@
                        'dict2': { 'userdef1': 'UserDefOne', 'string2': 'str' },
                        '*dict3': { 'userdef2': 'UserDefOne', 'string3': 'str' } } } }
 
+# for testing unions
+{ 'type': 'UserDefA',
+  'data': { 'boolean': 'bool' } }
+
+{ 'type': 'UserDefB',
+  'data': { 'integer': 'int' } }
+
+{ 'union': 'UserDefUnion',
+  'data': { 'a' : 'UserDefA', 'b' : 'UserDefB' } }
+
 # testing commands
 { 'command': 'user_def_cmd', 'data': {} }
 { 'command': 'user_def_cmd1', 'data': {'ud1a': 'UserDefOne'} }
diff --git a/scripts/qapi-types.py b/scripts/qapi-types.py
index b56225b..727fb77 100644
--- a/scripts/qapi-types.py
+++ b/scripts/qapi-types.py
@@ -117,6 +117,7 @@ struct %(name)s
 {
     %(name)sKind kind;
     union {
+        void *data;
 ''',
                 name=name)
 
@@ -269,6 +270,7 @@ for expr in exprs:
     elif expr.has_key('union'):
         ret += generate_fwd_struct(expr['union'], expr['data']) + "\n"
         ret += generate_enum('%sKind' % expr['union'], expr['data'].keys())
+        fdef.write(generate_enum_lookup('%sKind' % expr['union'], expr['data'].keys()))
     else:
         continue
     fdecl.write(ret)
@@ -283,6 +285,10 @@ for expr in exprs:
         fdef.write(generate_type_cleanup(expr['type']) + "\n")
     elif expr.has_key('union'):
         ret += generate_union(expr['union'], expr['data'])
+        ret += generate_type_cleanup_decl(expr['union'] + "List")
+        fdef.write(generate_type_cleanup(expr['union'] + "List") + "\n")
+        ret += generate_type_cleanup_decl(expr['union'])
+        fdef.write(generate_type_cleanup(expr['union']) + "\n")
     else:
         continue
     fdecl.write(ret)
diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py
index 5160d83..54117d4 100644
--- a/scripts/qapi-visit.py
+++ b/scripts/qapi-visit.py
@@ -110,10 +110,38 @@ def generate_visit_union(name, members):
 
 void visit_type_%(name)s(Visitor *m, %(name)s ** obj, const char *name, Error **errp)
 {
-}
+    Error *err = NULL;
+
+    visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(name)s), &err);
+    visit_type_%(name)sKind(m, &(*obj)->kind, "type", &err);
+    if (err) {
+        error_propagate(errp, err);
+        goto end;
+    }
+    switch ((*obj)->kind) {
 ''',
                  name=name)
 
+    for key in members:
+        ret += mcgen('''
+    case %(abbrev)s_KIND_%(enum)s:
+        visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, "data", errp);
+        break;
+''',
+                abbrev = de_camel_case(name).upper(),
+                enum = de_camel_case(key).upper(),
+                c_type=members[key],
+                c_name=c_var(key))
+
+    ret += mcgen('''
+    default:
+        abort();
+    }
+end:
+    visit_end_struct(m, errp);
+}
+''')
+
     return ret
 
 def generate_declaration(name, members, genlist=True):
@@ -242,6 +270,7 @@ for expr in exprs:
         fdecl.write(ret)
     elif expr.has_key('union'):
         ret = generate_visit_union(expr['union'], expr['data'])
+        ret += generate_visit_list(expr['union'], expr['data'])
         fdef.write(ret)
 
         ret = generate_decl_enum('%sKind' % expr['union'], expr['data'].keys())
diff --git a/test-qmp-input-visitor.c b/test-qmp-input-visitor.c
index 926db5c..1996e49 100644
--- a/test-qmp-input-visitor.c
+++ b/test-qmp-input-visitor.c
@@ -234,6 +234,22 @@ static void test_visitor_in_list(TestInputVisitorData *data,
     qapi_free_UserDefOneList(head);
 }
 
+static void test_visitor_in_union(TestInputVisitorData *data,
+                                  const void *unused)
+{
+    Visitor *v;
+    Error *err = NULL;
+    UserDefUnion *tmp;
+
+    v = visitor_input_test_init(data, "{ 'type': 'b', 'data' : { 'integer': 42 } }");
+
+    visit_type_UserDefUnion(v, &tmp, NULL, &err);
+    g_assert(err == NULL);
+    g_assert_cmpint(tmp->kind, ==, USER_DEF_UNION_KIND_B);
+    g_assert_cmpint(tmp->b->integer, ==, 42);
+    qapi_free_UserDefUnion(tmp);
+}
+
 static void input_visitor_test_add(const char *testpath,
                                    TestInputVisitorData *data,
                                    void (*test_func)(TestInputVisitorData *data, const void *user_data))
@@ -264,6 +280,8 @@ int main(int argc, char **argv)
                             &in_visitor_data, test_visitor_in_struct_nested);
     input_visitor_test_add("/visitor/input/list",
                             &in_visitor_data, test_visitor_in_list);
+    input_visitor_test_add("/visitor/input/union",
+                            &in_visitor_data, test_visitor_in_union);
 
     g_test_run();
 
diff --git a/test-qmp-output-visitor.c b/test-qmp-output-visitor.c
index c94c208..78e5f2d 100644
--- a/test-qmp-output-visitor.c
+++ b/test-qmp-output-visitor.c
@@ -380,6 +380,38 @@ static void test_visitor_out_list_qapi_free(TestOutputVisitorData *data,
     qapi_free_UserDefNestedList(head);
 }
 
+static void test_visitor_out_union(TestOutputVisitorData *data,
+                                   const void *unused)
+{
+    QObject *arg, *qvalue;
+    QDict *qdict, *value;
+
+    Error *err = NULL;
+
+    UserDefUnion *tmp = g_malloc0(sizeof(UserDefUnion));
+    tmp->kind = USER_DEF_UNION_KIND_A;
+    tmp->a = g_malloc0(sizeof(UserDefA));
+    tmp->a->boolean = true;
+
+    visit_type_UserDefUnion(data->ov, &tmp, NULL, &err);
+    g_assert(err == NULL);
+    arg = qmp_output_get_qobject(data->qov);
+
+    g_assert(qobject_type(arg) == QTYPE_QDICT);
+    qdict = qobject_to_qdict(arg);
+
+    g_assert_cmpstr(qdict_get_str(qdict, "type"), ==, "a");
+
+    qvalue = qdict_get(qdict, "data");
+    g_assert(data != NULL);
+    g_assert(qobject_type(qvalue) == QTYPE_QDICT);
+    value = qobject_to_qdict(qvalue);
+    g_assert_cmpint(qdict_get_bool(value, "boolean"), ==, true);
+
+    qapi_free_UserDefUnion(tmp);
+    QDECREF(qdict);
+}
+
 static void output_visitor_test_add(const char *testpath,
                                     TestOutputVisitorData *data,
                                     void (*test_func)(TestOutputVisitorData *data, const void *user_data))
@@ -416,6 +448,8 @@ int main(int argc, char **argv)
                             &out_visitor_data, test_visitor_out_list);
     output_visitor_test_add("/visitor/output/list-qapi-free",
                             &out_visitor_data, test_visitor_out_list_qapi_free);
+    output_visitor_test_add("/visitor/output/union",
+                            &out_visitor_data, test_visitor_out_union);
 
     g_test_run();
 
