Since the late 1970s, social movement unionism (SMU) has emerged as a revitalizing alternative to the discredited unionism of the past. As such, the successful experiences of the Brazilian, South African, Filipino, and more recently the South Korean SMUs have been debated and analyzed by social scientists. Moreover, several SMU campaigns in North America appear as promising cases, in which labor unions collaborate with community-based non-union organizations. This chapter focuses on the Argentine experience of SMU. Although Argentine new social movements have attracted scholarly attention, recent developments in labor movements, in particular, union revitalization has been largely neglected as a topic of sociological inquiry. This chapter analyzes the Central of the Argentine Workers (CTA) as an SMU, and discusses the problems of labor revitalization. The case of Argentina is different from other well-known SMU experiences. The Argentine unionism engendered a powerful and militant labor movement solidly linked to a political party movement-Peronism. The Argentine SMU faces problems of building a new type of unionism due to the legacy of this former culture and of labor union institutions. I will fi rst summarize the conditions of the labor movement and unions in Argentina before the foundation of the CTA. Then, I will discuss the case of the CTA as an example of SMU, and, fi nally, I will analyze the Argentine case in relation to other well-known experiences.