This article chronicles the institutional development of IB teaching institutions within business schools and introduces dominant IB leaders that have shaped these evolutions. The chapter begins with a description of these developments based on vignettes from the memoir of the author (Classifying vignettes, modeling hybridity, University of Minnesota Press, 2019), which taken together create a vivid, yet subjective, description of the dynamics of this institutional development and form an overarching narrative of its historical evolution. Goodnows’ predominantly US-based recollection begins in 1946, when Thunderbird introduced the first IB curriculum in the US and probably in the world and continued throughout the 1980s and 1990s. The chapter concludes by presenting some important external developments that supported the institutionalization of IB teaching in business schools.