This chapter introduces the book's central research questions: what factors shaped the first interim governments in Tunisia and Libya, and what role did they play in shaping transitions? It also overviews the book's main arguments and explains its contribution to the existing literature. While a rich literature has debated the importance of pre-existing institutions (or structural variables) and actors' decisions (or agency variables) during political transition, to date scholarship has not examined how the two types of variables come together in the immediate aftermath of an anti-authoritarian uprising. Moreover, the literature has not looked comprehensively at the set of important decisions taken during this phase, such as defining a constitutional drafting process, defining an electoral process and rules, and establishing mechanisms for transitional justice.