Solution- focused therapy is a strength- based approach, emphasizing the resources people invariably possess and how these can be applied to the change process. A review was undertaken on the treatment outcome research involving solution- focused therapy to determine empirically its effectiveness. the review involved experimental or quasi- experimental designs conducted from 1985 to 2006 and was limited to published studies written in the English language. Subject, intervention and mythological information on studies were collected, as well as statistical information necessary to calculate effect sizes. After searching the literature, ten studies with high located and described. No particular characteristics emerged regarding studies with high versus low effect sizes. Implications for research are advanced based on the review, especially related to social work practice.