Sleep quality during adolescence and young adulthood are increasingly recognized as a common, yet understudied phenomenon, with significant impact on important health-related outcomes across the life-course, including impulsivity, risk taking, obesity, substance use, decision making, criminal justice system involvement and psychopathology. Like many other health-related risk disparities, poor sleep quality (PSQ) is particularly prevalent in low SES inner city neighborhoods. However, unlike many other risk factors for poor health-related outcomes, PSQ is potentially modifiable and could be a cost-effective target for public health intervention. The key to actualizing this potential requires understanding how PSQ relates to other childhood risk factors (various levels of environment: family, home, neighborhood), as well as learning how PSQ operates in conjunction with other factors, e.g., parental substance use, youth decision-making and genetics, etc., known to impact well- being. These interacting processes are particularly understudied during the important developmental stages of adolescence and young adulthood, a qualitatively distinct period for cognitive, emotional and physical development. We propose, therefore, to recruit a sample of youth (N=650) from our Stress and Justice (S&J) Study samples (R01-DA023733 and R01-DA024029, PI: Hoven), consisting of longitudinal investigation of high-risk, hard-to-reach, minority families living in the poorest Congressional District in the US, to conduct a study on the role of sleep in youth (ages 12-24). We will recruit the youth and one of their parents and then, over a 14 day period, obtain objective, continuous measures of the youth’s sleep (actigraphy) and their sleep environment (temperature, noise, and light), as well as the youth’s mental health status and a behavioral decision task will assess reward processing, delay discounting and cognitive control. In addition, we will conduct a comprehensive face-to-face assessment of both the youth and a parent concerning sleep problems, familial and social environment, as well as obtain objective neighborhood safety and quality (e.g., noise, air quality, etc.). Comprehensive data about these youth and their families previously collected as part of the S&J Study (two waves), as well as previously collected DNA, will be available to this Sleep Study. Together, with the high quality objective data collected here, will allow for testing a complex and highly informative model of the relationship of important risk factors for PSQ and its effects on important health- and mental health-related outcomes. By enriching understanding of the role that PSQ plays in the well-being of at-risk youth, this study will provide important information about behavioral entry points for targeted and effective interventions to improve sleep and therefore functional status and overall well-being.