In 1956, Dr. Albert Ellis presented his seminal work on Rational Therapy, subsequently renamed Rational Emotive Behavior Therapy (REBT) in 1993. This paper explores the origins, theoretical foundations, applications, and implications of REBT and provides a look at the empirical research available in support of the approach's efficacy. REBT is widely recognized as an effective approach to therapy. Many researchers have written on the usage of REBT, including Ellis himself who has authored over 700 articles and manuscripts relating to REBT. REBT is one of the cognitive-behavioral approaches to psychotherapy, in that it pays particular attention to the role that cognition and behavior play in the development and maintenance of people's emotional problems. Although REBT uses social learning theory and holds that external events and environmental influences significantly affect humans and contribute to their emotional disturbances, it stresses biological tendencies and innate predispositions; a view not held in other cognitive theories. Rational Emotive Behavior Therapy is presented as an effective approach for dealing with clients who have the ability and desire to make changes in their lives. The goal of REBT is not to rid people of their irrational beliefs, rather it is to minimize their emotional disturbances and self-defeating behaviors by acquiring a more realistic and workable philosophy of life. (Contains 31 references.) (GCP)