The Institutional Revolutionary Party (Spanish: Partido Revolucionario Institucional, PRI) is a Socialist-leaning political party in Mexico founded in 1929. It held power in the country for 71 years from 1929 to 2000, first as the National Revolutionary Party (Spanish: Partido Nacional Revolucionario, PNR), then as the Party of the Mexican Revolution (Spanish: Partido de la Revolución Mexicana, PRM), and finally renaming itself as the Institutional Revolutionary Party in 1946.
The most recent President from PRI was Enrique Peña Nieto. Former presidents under PRI include: Pascual Ortiz Rubio, Lázaro Cárdenas, Adolfo López Mateos, Gustavo Díaz Ordaz, Luis Echeverría Álvarez, José López Portillo, Miguel de la Madrid, Carlos Salinas de Gortari and Ernesto Zedillo.