This article analyses the experience of the “Central de Trabajadores de la Argentina” which emerged as an alternative to the traditional “Confederación General del Trabajo” and as a response to the historical conditions imposed on Argentina during the nineties. From a perspective that is focused on the political logic (union, hegemonic, partisan and populist), we rebuild the history of the CTA to contribute to the comprehension of its configuration as an actor and its breaking into two after the union elections 2010.