Guillermo Alberto O'Donnell Ure was born in Buenos Aires, Argentina to a family of Irish descent from County Donegal.

He earned his master's degree in political science in 1971, but rather than complete his dissertation and take a job offer from Harvard University, he returned to Buenos Aires.

And thus O'Donnell would not receive his Ph.D in political science from Yale University until he presented a new dissertation and thus was awarded his Ph.D. belatedly, once he was an established scholar and professor, in 1987.

[8][citation needed] In Argentina, O'Donnell initially taught at the Universidad del Salvador (1972–75) and was a researcher at the Centro de Investigaciones en Administración Pública (CIAP), at the Torcuato di Tella Institute, between 1971 and 1975.

[citation needed] During this period, Argentina was increasingly swept by violence, as guerrilla organizations such as the Montoneros sought to undermine the government and eventually the military rulers came to power in 1976 and launched a dirty war.

The project began with three conferences, in 1979, 1980, and 1981, that gathered many of the world’s most distinguished scholars of democracy, including Robert A. Dahl, Juan Linz, Adam Przeworski, Fernando Henrique Cardoso, and Albert Otto Hirschman.

Thereafter, though he maintained his affiliation with CEBRAP until 1991, he taught at the University of Notre Dame from 1983 until 2009, where he was Helen Kellogg Professor of Government and International Studies.

At UNSAM O'Donnell founded the Centro de Investigaciones sobre el Estado y la Democracia en América Latina (CIEDAL), in 2010.

The central contributions to this debate were published in a volume edited by David Collier, The New Authoritarianism in Latin America (1979),[7] which assessed and critiqued O’Donnell’s thesis.

His book, co-authored with Philippe Schmitter, Transitions from Authoritarian Rule: Tentative Conclusions about Uncertain Democracies (1986), was a widely-read and influential work in comparative politics during the 1980s and 1990s.

O'Donnell and Schmitter proposed a strategic choice approach to transitions to democracy that highlighted how they were driven by the decisions of different actors in response to a core set of dilemmas.

This book not only became the point of reference for a burgeoning academic literature on democratic transitions, it was also read widely by political activists engaged in actual struggles to achieve democracy.

Later work centered on the problems faced by most Latin American democracies as a result of deficiencies in the rule of law and the social capabilities of citizens.

[33] Summing up his contributions, one observer states that "O’Donnell decisively shaped the intellectual agenda for the study of the rise of military dictatorships in the Southern Cone in the early 1970s; pioneered the analysis of authoritarian breakdowns and democratic transitions throughout the 1980s; and broke new conceptual ground for efforts to understand the problems of life after transition (including the issue of institutional quality) during the 1990s.