In these times national unions seem to be out of breath under the wave of globalization, on which multinational firms surf quite well. But this is a false perception nowadays, when global unions begin to appear everywhere discussing, orienting and bargaining with their counterparts. The essay reflects about several types of unions’ intervention in the global scenario: international coordination of a global counterpart; transnational solidarity; incorporation to a judicial solution; transnational collective bargaining; and transnational mediation and arbitration. All five types of activities become presented under a significant case, not always finished with a unions victory.