This papers compares Portugal and Spain in order to isolate the factors able to explain varying patterns of associational life in post-authoritarian democracies. When compared with established and older democracies, Portugal and Spain have the weakest and least developed associational life (rates of affiliation, organizational development, and federative structures), which constitutes a legacy of the long period of authoritarianism. The state-corporatist Iberian authoritarian regimes left a legacy of localistic, individualistic, passive, and uncoordinated civil society that has lasted to the present day. Yet, not all post-authoritarian civil societies are condemned to be weak. In spite of lower levels of socioeconomic development, Portugal provides a more open and supportive institutional environment to civil society and citizen civic participation. We argue that differences in associational life between Portugal and Spain are the result of the breadth of liberalization of the dictatorships (mid-1960’s to mid-1970’s) and the processes of regime-building, namely the mode of transition from authoritarianism (mid-1970’s to early 1980’s).