Emphasis is placed on the use of empirically supported therapies in clinical practice as a manifestation of the scientist-practitioner approach. The predominant model used to provide empirical support for interventions uses groups of patients in randomised clinical trials in university settings. This model has severe limitations for the clinician. It cannot be assumed that results obtained in university-based, group studies generalise to a clinical practice setting. In addition, the group model does not provide the clinician with a practical approach to evaluate his/her intervention. Single case (N = 1) designs have much to offer the clinician in this regard. Clinicians need to be encouraged to use this approach in evaluating their interventions and journal editors should be encouraged to publish them.