The health professional’s ability to apply theories of health behavior is one of the most critical skills needed in designing programs to address contemporary public health problems, virtually all of which address important underlying behavioral risk and protective factors. The PRECEDE-PROCEED planning model can help to put these skills in action. Although the emphasis in PRECEDE-PROCEED has been on its utility for programs delivered in practice settings, the framework has also been useful to researchers conducting health behavior change intervention trials, which we will illustrate in the case studies presented in this chapter.