The Harvard political science professor Samuel P. Huntington (1927–2008) made visits to Brazil in 1972 and 1974 to advise the government about ‘decompression’ or regime liberalisation. The literature on Brazil's dictatorship references these visits as having had a major causal impact. This article argues that his influence on Brazilian regime change is greatly exaggerated. It also argues that Huntington, who became a leading theorist of democratisation, had an interest in and commitment to democracy that was more recent and circumstantial than is often thought. This helps to explain the current period of democratic ‘deconsolidation’ associated with the rise of authoritarian national populism in Brazil.