Single-subject research designs, with their concentration on the individual subject over extended time durations, are similar in form to the design of therapy and have been represented as the best, if not the only, appropriate method for carrying out clinical research. Despite the similarity between single-subject research sessions and clinical sessions, it is argued that such designs are not intrinsically more appropriate than group designs for clinical research. Single-subject and group research strategies are alternative and often competing approaches to the same research question, and the choice resides as much in the predilections of the researcher as in any intrinsic advantage in one or the other research strategy.