Albert Ellis's rational-emotive therapy (RET) is scrutinized on several conceptual and empirical grounds, including its reliance on constructive assessment and its ethical stance. Its professional impact thus far exceeds its scientific status. Opinion varies on how even to define irrational beliefs; 1 consequence is problems in assessing them. Meta-analytic reviews provide support for the general utility of RET, but more qualitative reviews question both the internal and external validity of much of the published research. Lacking are process studies that can shed light on the mechanisms of therapeutic change, a situation likely due to the complexity of RET and to a lack of consensus as well about its very definition. Perhaps more progress can be achieved by forsaking studies of RET as a package and shifting instead to examination of specific therapeutic tactics in particular circumstances.