The MAP Study is a longitudinal epidemiological study that follows 345 youth ages 14-17 who are involved with child protective services in Toronto over 2.5 years. It aims to describe their health, development trajectories, and examine factors linking maltreatment to outcomes. Initial findings show MAP youth experience higher rates of physical and sexual abuse, emotional and physical neglect compared to national averages. They also exhibit poorer physical health, more residential instability, lower school achievement, less employment, higher substance use, earlier risky sexual behavior, and greater depression and suicidal ideation. Caseworkers' ratings of youth functioning did not predict later suicide attempts, but youth self-reports of ongoing suicidal thoughts did.