This study will investigate the relationships among neighborhood characteristics, a mother’s perceptions of neighborhood characteristics, and her willingness to let her child play outdoors. Additionally, it will relate all of those factors to the child’s actual time spent playing outdoors.  This project will use newly-available data from the Fragile Families and Child Wellbeing Study, a longitudinal birth cohort study of mostly low-income U.S. children living in 20 large U.S. cities. Mothers were asked about neighborhood safety and social cohesion, and interviewers assessed the level of social disorder in the block around the child’s home. To supplement the existing data, investigators will collect detailed, neighborhood-level crime data from federal crime statistics and city police departments, and also construct neighborhood-level sociodemographic measures using U.S. Census data.