In recent years, dozens of grassroots unions have appeared in Greece, which are particularly attractive to both young workers and migrant workers. They are also committed to collective bargaining, deeply democratic and participatory, and attach great importance to the activism of the members that form their basis. (Kretsos, b., 2011, Vogiatzoglou, 2014) In Spain as in Greece, the two major confederations, UGT and CCOOs, miss the old days of collective bargaining, failing to respond to employer attacks and losing demobilized members. (Köhler and Jiménez, 2010, Roca, 2016). In contrast to the large unions, however, the smaller radical unions CGT, and CNT during the crisis significantly increased both their members and the ability to mobilize (Roca, 2016). These unions refer to anarcho-syndicalism and are divisions of the historical CNT of the civil war. Since in Greece we have the re-emergence of anarcho-syndicalism that dominated the labor union movement in Greece in its beginnings and other forms of alternative radical trade union action, we attempt through qualitative semi-structured interviews with members of grassroots unions in Greece and Spain. to their participation in the labor movement and even in institutionalized trade unions seeking to break with the dominant trade unionism. To see similarities and differences in how they experience the mobilization in basic trade unionism, their relationship with both the big unions and the wider social movements (feminist, ecological, etc.) and the prospects for the development of cinematic trade unionism especially in its current environment. acute economic and social crisis. (2016-01-01)