This comprehensive yet brief overview of the adolescent human brain discusses how the brain develops during this critical period of life, and how that development impacts decision making and risk-taking behavior in the adolescent. This originated as a white paper requested by the Canadian government for a specific group looking to understand adolescent brain development in the context of adolescent behavior. The paper was not made available to the Canadian government outside of the specific task force that requested it nor to the general public. The authors have since decided that having put so much effort into concisely summarizing research on adolescent brain development, it would be a useful addition to researchers in psychology generally. The original paper has since been updated and revised considerably.