 Intervention: the patients are instructed in the use of Mandometer at their first visit to the clinic and they are given a Mandometer for use at home over the following week. They are encouraged to eat the foods they normally eat for lunch and dinner on five days of the week. 75 of the 166 patients had up to six meals with Mandometer in these tests. The average amount of food and the time to eat thus collected on Mandometer are loaded onto Mandobase, a custom made database used in the clinical practice of the Mandometer Clinic. The data are used to program Mandometer with training curves for the control of eating behavior, i.e., amount of food eaten and duration of the meal. The aim of Mandometer training is that patients should eat about 300-350 g of food for both lunch and dinner at a speed of about 25-30 gmin. These values correspond to those of previously tested normal weight, healthy control subjects, who ate using Mandometer in a research laboratory, but never at home. Patients are also provided with a schedule for 24-hour food intake, in which regularity of eating is stressed and between meal snacking is discouraged. Patients return to the Mandometer Clinic every sixth week for measuring their body weight and their eating behavior using Mandometer without training curves. The 188 patients who did not use Mandometer at home had their training curves similarly prepared but based on one test with Mandometer only, which was administered as part of their eating examination when they were admitted to the clinic. The patients are treated as out-patients, they come onceweek over the first eight weeks and then oncesecond week. The average number of visits to the clinic is 30 over about a year. 