This chapter studies the evolution of Chilean firms’ organizational form during the Pinochet regime (1973–1990). In particular, Felipe Aldunate focuses on Chilean business groups which, according to the literature, are the most important organizational structures at present in this country. He presents evidence on the existing business groups by 1973, and the disruption created by the 1982 financial crisis in terms of the destruction of old business groups and the creation of new groups. Felipe also studies how the different privatization waves implemented by the Pinochet regime affected business groups’ formation.