The paper analyzes four cases of IAS adoption (Aérospatiale in 1989; Usinor in 1991; Coflexip in 1993; and Péchiney in 1995) to better understand the instructional logics behind the use of alternative or additional standards by French companies in the early 1990s. The design of the study employs multiple case studies to explain how and why the heterogeneity of adoption (IAS versus US GAAP) is a response to institutional complexity. This research shows that French companies adopted IAS as long as they were not required to use US GAAP by their financial backers. The results highlight how the companies combine several logics to respond to the complexification of the field. The authors outline how the endorsement of distincts logics by outside carriers (auditors, financial analysts, stock exchange commissions) and framing of logic by managers evolve in time and space within this complexification process. The implications are numerous. This study contributes to the institutional complexity literature in that it focuses on distinct organizational responses to multiple institutional logics. More precisely, the choice of standards in primary consolidated accounts are viewed as an organizational response to compatible and conflicting demands from several levels: home countries, transnational areas, and host countries with the aim of raising funds in the US. The originality of the research is that it makes a distinct link between institutional complexity and international accounting standards and US GAAP.