General practitioners using DSM-III criteria have studied the incidence and prevalence of anorexia nervosa and bulimia nervosa in a large (N = 151,781) representative sample of the Dutch population. The incidence rate for anorexia nervosa is 6.3 and for bulimia nervosa 9.9 per year per 100,000 population. The prevalence of bulimia nervosa is three times higher in larger cities than in smaller urbanized or rural areas, while anorexia nervosa is found with almost equal frequency in areas with a different degree of urbanization.