Noting that there are an estimated 1.2 billion 10- to 19-year-olds in the world, this report examines the challenges faced by adolescents in both developing and developed nations. The report describes adolescence as a complex transition during which youth take on new responsibilities and experiment with independence. The importance of the development and reorganization of areas of the brain responsible for planning, organization, judgement, problem solving, and emotional control is discussed. The report asserts that as adolescents undergo this fascinating journey, they need access to information, skills, and services. It is argued that they need to feel safe, supported, and connected to adults in their lives. The report asserts that society has an obligation to shepherd its youth through their adolescent years and to treat them with respect and understanding. When society assumes these responsibilities, the benefits multiply in ways never imagined. Quotations from youth illustrate various frustrations and pressures they encounter. The report also describes the impact of several life skills educational programs in developing countries. The UNICEF Web project linking youth from diverse social classes and economic backgrounds from all over the world is also described. The report concludes with a section, "You Need to Know...," delineating facts on HIV/AIDS, sexuality, pregnancy, childbearing, violence and exploitation, smoking, drug and alcohol use, mental health and suicide, working and employment, and nutrition. (KB)