Institutional Revolutionary Party
The Institutional Revolutionary Party (, PRI) is a Mexican political party founded in 1929 that held uninterrupted power in the country for 71 years from 1929 to 2000, first as the National Revolutionary Party (, PNR), then as the Party of the Mexican Revolution (, PRM), and finally renaming itself as the Institutional Revolutionary Party in 1946.
Institutional Revolutionary Party
Though it is a full member of the Socialist International (along with its rival, the left-wing PRD; Mexico is one of the few nations with two major, competing parties that are part of the same international grouping), the PRI is not considered a social democratic party in the traditional sense.