The aim of this paper is to investigate the relevance of individual, product and situational determinants of organic food buying behavior in three industrialized (USA, Canada, and Germany) and two transition societies (Russia and Ukraine). In total 967 consumers were interviewed. In a review of extant literature on organic buying behavior, three categories of influencing factors were discovered and integrated in the theory of planned behavior: personspecific, situation-specific and product-specific factors. To test the model empirically multi-group structural equation modeling is applied. Results of this study provide evidence of universal and country-specific factors. Positive attitudes toward organic food and social norms are important drivers of organic food consumption across all nations. However, marketers should distinguish between attitudinally (e.g., USA) and normatively controlled target markets (e.g., Ukraine). Price tolerance fosters intentions and behaviors throughout all samples. Availability, im