Adolescents and young adults make up over a quarter of the global population. They can also be considered the most pervasively neglected group in global health. Yet a quiet revolution is now bringing a recognition that adolescents are central in almost every major challenge in global health. Bringing greater visibility to adolescents and their health has been an important facet of that recognition. This is also a central theme of the new Lancet Commission on Adolescent Health and Well-being. This presentation will track progress in our understandings of adolescent health and major influences on health over these years. It will also address currently available global data, gaps, and potential solutions. The Global Burden of Disease Study in particular has an important role in the new Commission and in guiding the development of better health information systems for this age group.