The paper explores the role of interfirm diversity in global strategic alliances (GSAs) and its impact on alliance longevity and effectiveness. It argues that while diversity can hinder cooperation, it is essential for alliance formation and maintenance. The study develops a multilevel typology of interfirm diversity, distinguishing between Type I (strategic and complementary differences) and Type II (negative differences that hinder performance). Type I diversity is crucial for alliance formation, while Type II diversity can be mitigated through organizational learning and adaptation. The paper emphasizes the importance of organizational learning in managing diversity, with learning enabling partners to adapt and improve collaboration over time. It also highlights the need for structured mechanisms to enhance behavior transparency and the importance of cultural, national, and corporate-level differences in shaping alliance outcomes. The study concludes that while diversity can pose challenges, effective learning and adaptation can lead to successful and long-lasting GSAs. The paper calls for further research on the dynamics of diversity and learning in GSAs, emphasizing the need for a systematic framework to understand and manage interfirm diversity.The paper explores the role of interfirm diversity in global strategic alliances (GSAs) and its impact on alliance longevity and effectiveness. It argues that while diversity can hinder cooperation, it is essential for alliance formation and maintenance. The study develops a multilevel typology of interfirm diversity, distinguishing between Type I (strategic and complementary differences) and Type II (negative differences that hinder performance). Type I diversity is crucial for alliance formation, while Type II diversity can be mitigated through organizational learning and adaptation. The paper emphasizes the importance of organizational learning in managing diversity, with learning enabling partners to adapt and improve collaboration over time. It also highlights the need for structured mechanisms to enhance behavior transparency and the importance of cultural, national, and corporate-level differences in shaping alliance outcomes. The study concludes that while diversity can pose challenges, effective learning and adaptation can lead to successful and long-lasting GSAs. The paper calls for further research on the dynamics of diversity and learning in GSAs, emphasizing the need for a systematic framework to understand and manage interfirm diversity.