Gender discrimination impedes girls and young women, especially in today’s youdi-dominated populations. Girls and young women face the largest gaps between their enrolment in secondary school—a critical gateway to participation in society and the economy. Similarly, they face overall discrimination that further inhibits their engagement and contributions to their families, communities and the larger society, as illustrated by comparing percentages of young people in country populations and those countries’ rankings on a United Nations Development Programme index of gender discrimination. This is especially harmful because good health paves the way to economic opportunity, long life, and overall well-being. In most countries, their numbers compound challenges in escaping violence, in finding dignified work, or in gaining access to decent schooling and youth-friendly health services, including reproductive health and family planning services. Among the most promising strategies for spurring national development and improving the prospects of young people are energetic and well-timed investments in education, health—including sexual and reproductive health—and women’s status.