He argued that the form of authoritarianism experienced by South America starting in the 1960s was novel because it was based on modern technocrats and a professionalized military organization, instead of populist politicians or traditional military strongmen.
To capture this distinctiveness, he coined the term 'bureaucratic authoritarianism'.
Dahl, Juan Linz, Adam Przeworski, Fernando Henrique Cardoso, and Albert Otto Hirschman.
It would result in a landmark publication: Transitions from Authoritarian Rule. In late 1979, O'Donnell left Argentina again, this time for Brazil.
There he continued to be active on the local academic scene.
He joined the Escuela de Política y Gobierno, at the National University of General San Martín (Universidad Nacional de San Martín [UNSAM[), his last professional affiliation.
He worked with the United Nations Development Programme (UNDP) during the 2000s, collaborating with Dante Caputo in the preparation of the United Nations Development Programme’s (UNDP) report Democracy in Latin America.
Toward a Citizens’ Democracy (2004), O'Donnell returned to his native Buenos Aires in 2009.
At UNSAM O'Donnell founded the Centro de Investigaciones sobre el Estado y la Democracia en América Latina (CIEDAL), in 2010.
and his remains were buried in the Recoleta Cemetery.