This chapter delves deeper into the role of environmental influences, without forgetting that environmental influences always play their role in the context of gene–environment correlations and interactions. The environments (i.e., experiences) that, on average, are statistically correlated with a higher risk are easy to identify in studies. They include stressful events, including trauma and economic hardship, maladaptive family and neighborhood environments, racial discrimination, and some characteristics of family environments. Environments do not passively shape behavior into psychological problems, however. People actively transact with their environments, meaning that their environments influence their behavior, their behavior and other characteristics influence their environments, and their characteristics moderate the extent to which their experiences influence their behavior. Many characteristics influence people’s transactions with the environment, including age, sex, race, and ethnicity. It is also useful to examine broad individual differences in cognitive and emotional traits, termed dispositions, which play key roles in people’s transactions with the environment that result in psychological problems. One important aspect of this is that many people engage in stress generation, in which their behavior actively creates stressful events such as conflicts with others that in turn stress the people who engage in the stress generation.