Experience with depot medroxyprogesterone acetate as a contraceptive preparation in 7 335 patients for a total of 38 714 months over a 3-year period is described. The discontinuation rate was 18.3% and the failure rate 0-35 per 100 women-years of use. This compares very well with all other methods of contraception. The only troublesome side-effect was breakhrough bleeding which diminished with continued use. The aetiology of this menstrual disruption and methods of prevention and treatment are discussed. The role of this preparation in present-day contraceptive practice is outlined.