The article examines how and why a new independent trade union was established in McDonald’s Japan in 2006. We discuss these developments both within the McDonald’s ‘system’ and the broader context of the growth of community unions in the Japanese employment system. The findings suggest that the ‘McUnion’ could be seen as a new form of trade union organizing in Japan; unlike an enterprise union it is independent of the employer and recruits ‘non-regular’ workers, yet unlike most community unions is established in one large employer, on a national rather than regional basis, has largely retained its membership and was established and operates with the direct involvement of the main Japanese Trade Union Confederation, Rengo.