Combinations of treatment are used increasingly in child and adolescent therapy research, following a pattern long evident in clinical practice. The present article evaluates the multiple influences leading to the use of combined treatments, different ways in which treatments are combined, and challenges that combined treatments raise for research and practice. The central thesis is that combined treatments are unlikely to contribute to treatment outcome unless there are significant changes in the way research is conceptualized and conducted. Limitations in methods of combining treatment, the absence of explicit and empirically defensible decision rules for individually tailored treatments, perpetuation of current limitations in the ways treatments are tested and delivered, and methodological obstacles for evaluating combined treatments are used to bolster the thesis. Recommendations are made for Improving research on combined treatments, such as investigating the decision‐making process guiding the combinations of treatment, the constituent techniques that are used to form combinations, novel models of delivering services to bolster outcome, and processes and mechanisms of therapeutic chang