As more funding becomes available for community programs designed to promote youth development, higher expectations are being placed on programs to demonstrate (and not just to proclaim) that they do indeed promote the healthy development of youth. Well-established programs that draw on public funds are being adopted in cities and communities throughout the United States. Increasingly, these programs are being expected to demonstrate that they actually do make a difference in young people’s lives. It is precisely because these programs are being established in a wide variety of communities that it is important to know if they make a difference and, if so, under what conditions and for whom. Moreover, given the recent call for significant investments in public resources, it would betray public trust not to document the steps taken to implement these programs and to provide evidence of the effectiveness of programs.

How should one think about evaluation of community programs for youth in the future? What social indicators exist that help us understand community programs for youth? What else is needed in order to better understand and evaluate these programs?

Part III explores the various methods and tools available to evaluate these programs, including experimental, quasi-experimental, and nonexperimental methods. Each method involves different data collection techniques, and each affords a different degree of causal inference—that is, whether a particular variable or treatment actually causes changes in outcomes. Findings from evaluations using these methods were incorporated into Part II. We turn now to exploring evaluation methodologies in more detail, looking specifically at the role for evaluation (Chapter 7) and data collection (Chapter 8) for the future of these programs.

There are particular challenges inherent to evaluating community programs for youth. Many of them tend to be relatively new and are continually changing in response to growing interest and investments on the part of foundations and federal, state, and local policy makers. In addition, the elements of community programs for youth rarely remain stable and consistent over time, given that program staff are always trying to improve the services and the manner in which they are delivered. Moreover, some programs struggle to overcome barriers during the implementation phase—for example, to receive a license or permits, to acquire appropriate space or renovate a facility, or to recruit appropriate staff and program participants. As a result, early implementation of