The National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (SECCYD) is a comprehensive study of human development that has followed participants from birth (N = 1,364) to age 26 (N = 814). Observations, diagnostic procedures, standardized tests, and questionnaires were used to measure five developmental contexts (early care and education, home, school, out of school, and neighborhoods) and three developmental domains (social–emotional, cognitive–academic, and physical–biological). Measures were repeated over time so that stability, change, and growth trajectories of both contexts and developmental domains could be studied. The goals of this review are threefold: (a) to acquaint readers with the depth and breadth of measures available in this public data set, (b) to provide an overview of longitudinal findings that extend the SECCYD to the end of high school and age 26, and (c) to highlight promising areas for future research. (author abstract)