Employing a methodology of talking and listening across national borders, this chapter analyzes the path activism in Left organizations between 1960 and 1990. The evidence for this analysis comes from oral histories of militants from varied organizations and different countries in Latin America. Militants went through a process of politicization before becoming so, and to understand that process, the categories of experience and ideology are used to analyze oral sources. The analysis allows us to see how experience and ideology are constitutive of militant practice. The chapter compares similarities in individual trajectories, though not regarding organizations or political positions, as is usually done. Instead, the chapter first examines similarities regarding the narrative form to convey memories and then looks at what in fact is told, which starts with vague contacts with politics and ends in hardened commitment to Left-wing activism and organization. The piece then goes on to explore the inversion of meaning that turned hegemonic ideas into rebellious ideas, thus adding dynamism to what was normally studied as the acquisition of an already elaborated Left ideology. Finally, this chapter analyzes how expectations constructed by socialization in the dominant culture do not correspond with lived experience, focusing our attention on those breaks and the effort to interpret novel perceptions. This chapter argues for the necessity to understand the dialectical relationship between experience and ideology over time in order to learn how individuals become political, a process that led militants to break with static ideologies in the past, and continues to do so as they remember and reflect on the past.