The three major tour operator associations in the U.S. are the National Tour Association (NTA), the United States Tour Operators Association (USTOA), and the American Bus Association (ABA). In Europe, there are the European Tour Operators Association (ETOA), and in the UK, the Association of British Travel Agents (ABTA) and the Association of Independent Tour Operators (AITO). The primary association for receptive North American inbound tour operators is the Receptive Services Association of America (RSAA).