Partido Mexicano Socialista

The Partido Mexicano Socialista (PMS) was the left - wing Mexican Socialist Party that emerged in 1988 from the Partido Socialista Unificado de México (PSUM) , which had merged with the Partido Mexicano de los Trabajadores (PMT) the year before .

In 1989, the PMS Cuauhtémoc Cárdenas Solórzanos and other representatives of the Partido Revolucionario Institucional (PRI) joined in founding the Partido de la Revolución Democrática (PRD).