Child and adolescent therapy has progressed considerably, as reflected in the sheer number of controlled studies, their methodological quality, and identification of empirically supported treatments. Even so, research is not likely to make significant advances, in light of the way in which treatment is studied and the emphasis on technique-focused questions. This article raises 3 questions: What are the goals of child and adolescent psychotherapy research? What type of research is needed to obtain these goals? How can we determine whether we are making progress toward the goals? This article provides a plan to advance research that (1) emphasizes understanding the mechanisms or processes through which therapeutic change occurs, (2) draws on developmental psychopathology research to inform treatment, (3) expands the range of questions that guide treatment research, and (4) elaborates multiple treatment outcomes on which to base conclusions. Recommendations are made to both develop the research agenda and to evaluate progress.