Behavior therapy is a cornerstone of weight loss treatment and behaviorists help direct patients' treatment. A novel design was used that allowed participants to choose different treatment modalities during behavioral weight loss treatment. The association between the selection of different treatment modalities and program completion was examined (N = 58). Participants could choose five additional treatments options (two medications with or without meal replacements, or meal replacements alone). Participants changed treatments 3.5 times on average. Participants who completed the study changed treatments significantly more times than dropouts. Dropouts, however, tried more treatment options early in treatment compared to completers. Over time, participants chose more effective treatments. The results provide behaviorists with data on the benefits and costs of patients changing treatment modalities during treatment. (Contains 2 figures and 3 tables.)