Sustainability is an increasingly relevant issue, especially for young adults that are deeply informed on topics of their interest, and also position themselves on social networks. Brands and companies currently offer a wide variety of sustainable products aimed at this cohort, whose attitudes are favorable to sustainable practices, however not frequently translating it into behavior. Considering this context, the present study conducted 13 in-depth interviews to explore motivational factors to beauty and personal care sustainable products purchase among 18-25 y.o. young adults from Sao Paulo, Brazil. Internal, social and external factors were mapped and subsequently analyzed in two codification cycles, complemented by an additional literature review. Results reinforce the importance of both normative and cultural social factors in this process, as well as embedded complexity in social reality of which this cohort is part of. This reality encompasses two simultaneous social environments (physical and digital), in which youngsters from Z generation interact, influence and are influenced as well. Comparing these environments indicated how social factors influence sustainable purchasing in each case.