Political science and constitutional law are useful tools to study the current process of democratic consolidation in Latin America. The first allows us to measure the phenomena which have made the transition and the consolidation possible (external influences, crisis of the economic model, social demand, regional integration?). As a complementary approach, the second allows us to understand the structural nature of the essential relationship between law and history in countries which, though very different, have experienced similar cycles since their independence in the 19th c., marked by early adhesion to democratic principles. [R]