Since the 1980s, when South America pulled away the shadow of authoritarianism and again to breathe the air of freedom, the democratization process has been strengthened in the region, within a very dynamic and not uniform among the states. In this chapter we describe the construction of regional democracy and the changes occurring every decade, including the prospects for this ongoing, with reference to the historical and political process of each South American State, including the ostensible expansion of citizenship rights and political involvement of citizen, but 186. GeoTextos, vol. 8, n. 2, dez. 2012. E. Carmo, S. Pacheco. 185-210 without ceasing to understand the fragility of political institutions, the drama of corruption, the obstacles posed by drug trafficking and the guerrilla groups, the constraints to economic growth and rising, but still incipient, organization of the Southern Common Market – Mercosul.