The book to be presented has a great value. In the first place it was a necessary publication, for both the academy as well as for the political life of our country. For the academy because the Partido de la Revolución Democrática (PRD) and the political parties and organizations that formed it have been the least studied in the wide range of political parties in Mexico. There are several works and researches on the PRI (Hernández, 1998; Garrido, 1994; Báez, 2001), several volumes on the PAN (Loaeza, 1999; Misrahi, 1998), but there are few texts on PRD or the Mexican left wing in general (Bartra, 1982; Bruhn, 1997, 1998; Carr, 1996). The academy gets shyly toward the analysis of the political parties after 1988, when numerous approaches on the hegemonic system-party start coming tolight, led by the works of Giovanni Sartori (1980) principally. Gradually start the research on the old and new parties. Nonetheless, to this approach a text that accounted for the origin, evolution, performance and perspectives of the Mexican transition heir, the PRD was missing. That is the reason why the book by Igor Vivero was, in the first place, definitely necessary.