Based on Boyce and Ellis's model on "context" and "biological sensitivity to the context", this article analyzes the interaction between the experience of daily hassles and experimentally induced cardiovascular reactivity as an indicator of stress reactivity, in explaining risk taking and self-esteem. This study found, in a sample of 599 adolescents, that (1. daily hassles were more strongly related to risk taking in boys and girls with high vs. low levels of cardiovascular reactivity and (2. taking into account the gendered experience of daily hassles was important in predicting outcomes for stress-reactive boys and girls. These results indicate that a biosocial approach may result in an increased understanding of the variability in the outcomes of stressors. (Contains 5 tables and 2 figures.)