This article addresses the way in which the Argentine Supreme Court has set out to redefi ne its own institutional role through its procedures and decisions, since its institutional reform in 2003. It shows that the Court has developed innovative ways of judicial intervention in public policy and rights issues, which include the participation of new kinds of actors and entail an emerging new relationship between the Court and civil society organizations in Argentina. The article argues that this change can be understood as a way for the Court to rebuild its institutional legitimacy, and that the reform is connected to the presence of strong nongovernmental organizations whose claims for a change in the Court's composition and procedures gained momentum in the aftermath of the social and political crisis of 2001-2002 in Argentina.