The unexpected and unforeseen fall of the Mexican one-party regime left an important question in the air: What could have possibly caused the collapse of the PRI after seventy years of enforcing a perfect dictatorship? And what does the Mexican experience contribute to our understanding of the breakdown of authoritarian regimes? These are the questions that animate this study. It is organized as follows: Part I reviews the literature on authoritarian breakdowns, with emphasis on O\u27Donnell\u27s argument of soft liners vs. hard liners, Linz and Lipset’s premise of regime legitimacy, and Huntington’s explanation based on economic development and modernization. Part II reviews these political science models of authoritarian breakdown and offers a critique in the light of the Mexican experience. Part III provides an alternative explanation to the fall of the PRI based on the idea of a political culture shift against the PRI at the national level. Finally, part IV offers a conclusion reflecting on what the Mexican experience and the fall of the PRI contribute to our understanding of authoritarian breakdowns
