Book excerpt: A wide body of research shows that consistent participation in high-quality afterschool and summer programs, also called out-of-school time or OST, provides substantial benefits to children and youth and their communities. Youth are more prone to engage in juvenile delinquency, substance abuse and other risky behaviors after 3:00 p.m. if there are few positive OST programs available. Municipal leaders are also well aware of the impact of high school dropout rates on crime and unemployment, and are increasingly supporting out-of-school learning opportunities as a strategy for promoting school and career success. This strategy guide provides cities with guidance on how to create enriching, relevant and supportive OST environments for middle and high school youth that will help put them on a path to success. The guide outlines key strategies that show the most promise for maximizing scarce local resources for the benefit of older youth, coupled with city examples from small, midsized and large cities. The practices described in the guide draw upon research on the unique developmental needs of middle and high school aged youth and what seems to work best in recruitment and retention of these youth. Ideas are presented for creating citywide "infrastructure" to help ensure that older youth not only attend OST programs, but do so at high rates of participation in order to maximize gains. Many of the ideas require little or no additional spending, but instead encourage creative use of partnerships and policies to achieve positive results for older youth. (Contains 8 resources and 17 footnotes.).