"Prevention" refers to efforts designed to reduce or eliminate outcomes that are harmful to youth and society. "Promotion" refers to efforts intended to achieve clearly defined positive outcomes or foster the development of skills and competencies in youth. "Productivity" refers to the effectiveness of a particular substantive service area in achieving desired outcomes, as well as the effectiveness of systems that are involved in working toward those outcomes. "Preparation" is the broadest of the four terms, since it is a general measure that cuts across the other three. How well-prepared youth are in areas such as work, family, and citizenship depends to a large extent on the success of the promotion and prevention experiences they encounter as well as the efficiency and productivity of the various systems that shape their lives. Three major themes emerge from this collection when read as a group: promoting youth development, building supportive communities, and reforming systems/linking services. References accompany some of the essays.