Early adolescence, age 10 to 14, is a pivotal moment in the lives of young girls and boys around the world. It is period of rapid development where important health and social knowledge is gained, lifelong behaviors are established, beliefs and attitudes are shaped, and the foundation is built for adulthood. This period offers a window of opportunity for program interventions to help shape the life trajectories of boys and girls and to improve the future physical and economic health and well-being of entire communities. Using recent analyses of DHS statistics from 71 low- and moderate-income countries, this report shines a spotlight on the distinctive needs of very young adolescents and the chief influences upon them, reviews the evidence around a broad range of program interventions and identifies areas for future research and action.