WHEREAS, The Society of Clinical Psychology is firmly committed to identifying and promulgating treatments that work.  Indeed, the Society was among the first organizations in mental health to compile a list of empirically supported treatments on the basis of supportive results from randomized clinical trials (RCTs). As scientific knowledge and research designs mature, and as researcher-practitioner collaborations increase, we have reached a point where it is desirable and feasible to extend the research methods used and the constructs investigated. A multiplicity of sophisticated research strategies, including but not limited to RCTs, now allows us to improve the effectiveness of psychological treatments.

THEREFORE, To advance this broad view, the Society of Clinical Psychology defines the mechanisms of psychotherapy as those factors, processes, and interventions that are designed to effect and maintain beneficial changes in client/patient functioning.  These change mechanisms include treatment methods,  participant characteristics,  the quality of their interactions (relationships), the context and culture in which the interventions occur,  and other contributors yet to be discovered.  This inclusive and evidence-based definition is designed to ensure that: 1) research on psychotherapy and the designation of empirically supported therapies consider  treatment methods as well as the participants, their relationship, and contextual factors; 2) a wide variety of research methods are used as appropriate to the questions asked;  and 3) research increases our understanding both of the cross-cutting/common and unique principles on which effective treatments rest and enhance the optimal use of participants, interactional, cultural, and technical factors in effecting change.