The debut of the Uruguayan left in government (2005-2010) inaugurated a social democratic alternative which joined the experiences of this kind emerging in Latin America at the start of the 21st century. The “third wave” of Latin American lefts, which began in 1999, has been characterized by manifestations of populism or popular nationalism, which are varieties of a recurrent political phenomenon in the region (Lanzaro 2006); although they have novel features and differ from their ancestors and among themselves. At the same time, in Brazil, Chile and Uruguay–with the presidencies of Lula da Silva, Ricardo Lagos, Michelle Bachelet and Tabaré Vázquez–governments of a social democratic character have emerged, which constitutes a true novelty in Latin America (Lanzaro 2008) 1.