This paper addresses the importance of affect regulation (AR) in relation to a broad range of behavioral and emotional health problems that emerge during adolescence. AR is defined as the adaptive modulation of emotional experience to serve a goal or purpose. This conceptualization of AR emphasizes the use of cognitive skills to guide, inhibit, or modify emotion and behavior, including the expression of emotional responses, in learned, strategic ways-skills that ultimately underpin adult levels of social maturity and the ability to show "responsible" behavior across a range of emotional situations. Neurobehavioral systems that subserve these AR skills include areas of the inferior and orbital prefrontal cortex (PFC), with rich interconnections to several limbic structures and other cortical areas, including the dorsolateral PFC. Adolescence represents an important developmental period in the functional maturation of adult AR skills; it is also a critical time in the development of clinical disorders of AR (eg, rates of depression increase dramatically and gender differences in depression emerge). Maturational changes in AR that occur during adolescence-particularly with respect to the role of emotions influencing responsible decision making-are also relevant to understanding key aspects of the developmental pathways of some behavioral health problems, such as alcohol use and nicotine dependence. A strong case is made for developmental research in affective neuroscience aimed at this important maturational period, particularly the kind of transdisciplinary research leading toward mechanistic understanding of the development of adolescent-onset disorders. Improving understanding in these areas could ultimately lead to the development of early interventions in targeted high-risk populations, and has enormous clinical and social policy relevance.