Despite the still frequently made assumption that humans are consistent, sophisticated, and selfish decision-makers, decades of research in the behavioral sciences suggest that individuals are often much less rational and egoistic than originally assumed. Yet, it is still elusive what causes variations in judgment, choice, and social behavior within and across individuals. One of the factors that may systematically influence decision-making is stress, or the underlying neuroendocrine stress response, respectively. In this session, Tobias will review recent findings in his lab on issues that alter decision-making, in particular social preferences.