Good results were obtained treating 49 obese patients with an elaborated selfcontrol behavior modification program. This program was an addition to the normal program of the obesity clinic of the 2. Medizinische Klinik der Universität Düsseldorf. The normal program contains some principles of behavior modification but less accentuated. After the initial 12 weeks of controlled training patients tried to reduce weight further decreasing external control. Only few patients were able to loose additional pounds during this period of 8 weeks. At the end of the initial 12 weeks patients had asked for another control before the vacational season, but only 10 out of 49 appeared at the control sessions 9 months after the program's start. If an additional behavior modification program is considered for incorporation into an already existing weight reduction clinic, additional costs and expected results have to be checked. Durative success of behavior modification techniques in weight loss programs has still to be submitted to proof.