This article grapples with two closely related tensions threatening the credibility and relevance of clinical trials to clinicians as well as patients and their families: (1) the tension between clinical flexibility and scientific standardization of protocol and (2) the tension between the need to ensure scientific integrity through a standard, pre-specified protocol and the need to increase compliance by involving patients and their families in goal setting and treatment planning. We propose four partial solutions: (1) relaxed exclusion criteria to maximize generalizability, using only those exclusion criteria essential to the treatment; (2) extensive use of clinical algorithms to incorporate clinical flexibility in a standardized way; (3) active involvement of therapists in decision-making, including cross-site clinical decision panels; and (4) active involvement of families through a goal-setting and treatment-planning session as the first step of treatment. Although we focus on clinical trials with children and adolescents, the principles and ideas may also apply to clinical trials with patients of any age. This article summarizes and elaborates on presentations made by three of the authors at workshops on psychiatric clinical trials in children and adolescents at the May 1996 New Clinical Drug Evaluation Unit (NCDEU) meeting. The focus was on enhancing the clinical relevance of clinical trials-making the results useful and credible to practitioners and patients and their families.