Research by the MacArthur-supported World Health Organization shows that while a number of interventions can help improve health outcomes in young people, there is no single action or intervention that can broadly meet the needs of all young people across geographies. The research focuses on three adverse health-related outcomes for young people – unintended and repeat pregnancy; child marriage; and sexually transmitted infections – and finds that while certain interventions, such as cash incentives to reduce child marriage, work in certain countries and for certain populations, no single approach improved outcomes in all populations and geographic settings.