This paper analyzes the resurgence of national-level social bargaining in two European states: Portugal and Spain. It argues that this development derives from the combination of two main factors: the weakening of trade union organizations at the branch and firm level, and the emergence of new institutions to promote tripartite social bargaining. These developments contributed to a transformation in the pattern of industrial relations. In both countries new emerging constraints and incentives to change largely determined the interaction and strategies of the social actors. In addition, in a new economic, political, and social environment the strategies of the social actors were less conditioned by pre-existing institutions. On the contrary, the changing balance of power affected their predisposition to pursue other strategies through a new set of institutions. Finally, the paper also examines the implications of the Portuguese and Spanish experiences for the broader debate on European Monetary Union.