This article explores how research on Central and Eastern Europe (CEE) has contributed to the development of theories in international business and management. Since the 1990s, CEE has provided unique societal quasi-experiments, allowing scholars to test the applicability of existing theories and develop new ones. Three main theoretical perspectives have emerged: organizational economics theories (including transaction cost theory and agency theory), resource-based theories, and institutional theories. These theories help explain key issues such as entry strategies of foreign investors, restructuring strategies of local incumbents, and entry and growth strategies of entrepreneurs. Organizational economics theories, such as transaction cost theory, have been applied to CEE, where institutions are less developed and uncertainty is high. These theories highlight the importance of institutional factors in shaping business strategies. Resource-based theories focus on the unique resources and capabilities that firms can use to gain competitive advantage. Institutional theories emphasize the role of institutions in shaping business strategies and outcomes. The research on CEE has shown that traditional theories may not be applicable in this context, and that new theories are needed to explain the unique challenges and opportunities in this region. The research has also highlighted the importance of contextual factors, such as institutions, in shaping business strategies and outcomes. The findings suggest that future research should focus on how institutions influence business strategies and outcomes, and how firms can adapt to these changes. The article also discusses the challenges faced by foreign investors in entering CEE, the restructuring strategies of local incumbents, and the entry and growth strategies of entrepreneurs. It highlights the importance of understanding the unique institutional context of CEE and how this influences business strategies and outcomes. The research has contributed to the development of new theories and has provided insights into how firms can adapt to the changing institutional environment in CEE.This article explores how research on Central and Eastern Europe (CEE) has contributed to the development of theories in international business and management. Since the 1990s, CEE has provided unique societal quasi-experiments, allowing scholars to test the applicability of existing theories and develop new ones. Three main theoretical perspectives have emerged: organizational economics theories (including transaction cost theory and agency theory), resource-based theories, and institutional theories. These theories help explain key issues such as entry strategies of foreign investors, restructuring strategies of local incumbents, and entry and growth strategies of entrepreneurs. Organizational economics theories, such as transaction cost theory, have been applied to CEE, where institutions are less developed and uncertainty is high. These theories highlight the importance of institutional factors in shaping business strategies. Resource-based theories focus on the unique resources and capabilities that firms can use to gain competitive advantage. Institutional theories emphasize the role of institutions in shaping business strategies and outcomes. The research on CEE has shown that traditional theories may not be applicable in this context, and that new theories are needed to explain the unique challenges and opportunities in this region. The research has also highlighted the importance of contextual factors, such as institutions, in shaping business strategies and outcomes. The findings suggest that future research should focus on how institutions influence business strategies and outcomes, and how firms can adapt to these changes. The article also discusses the challenges faced by foreign investors in entering CEE, the restructuring strategies of local incumbents, and the entry and growth strategies of entrepreneurs. It highlights the importance of understanding the unique institutional context of CEE and how this influences business strategies and outcomes. The research has contributed to the development of new theories and has provided insights into how firms can adapt to the changing institutional environment in CEE.