In order to confront a problem, it is crucial to understand it. Many fields of psychology-including community, social, clinical, counseling, developmental, school, and industrial and organizational psychology, among others-can contribute insights into the circumstances and dynamics that make individuals and communities vulnerable to human trafficking, as well as protective factors that decrease risk. These insights establish the groundwork for primary prevention efforts that proactively address risk, secondary prevention programs that guide identification and early response to incidents of human trafficking, and tertiary prevention responses that aim to reduce the incidence of recidivism and revictimization and mitigate its long-term impacts.Psychologist Urie Bronfenbrenner first developed the concept of a "socioecological model" in the late 1970s to describe how individuals affect, and are shaped by, a complex network of social influences and layered environmental contexts (Bronfenbrenner, 1979). Individuals are affected by both their immediate environments (e.g., families, schools, work settings, communities) and the larger social contexts within which these environments are embedded. Scientists are learning more about how social determinants of health-including social, economic, environmental, and structural