Male and female sterilization is a safe and effective form of permanent contraception. The number of patients accepting this method has rapidly increased over the last ten years and is likely to continue. In some countries the rate has plateaued out: in the USA it has been 31 per cent of all married women for the last eight years. Before sterilization it is important that adequate counselling is given to both partners and that the decision is not hurried. This is emphasized by the number of women and men requesting reversal of sterilization (thought to be between 0.1 and 10 per cent of all sterilizations). These requests for reversal usually come from couples who have remarried, tend to be younger, have fewer live children, have had more abortions, less schooling and are poor users of contraception. In these high-risk patients counselling and time to make the decision is essential. Other studies indicate that regret after puerperal sterilization may be commoner, but the risks of further pregnancies have to be weighed against sterilization regret. The methodology of male sterilization has changed little in the last ten years; it is simple and usually done under local anaesthesia. In contrast, female sterilization methods are constantly being refined, from laparotomy to laparoscopy and from extensive tubal destruction or excision to minimal tubal damage. The common methods now are mini-laparotomy and laparoscopy under local or general anaesthesia, with tubal occlusion by clips, rings or bipolar or thermal coagulation. There is no place now for unipolar diathermy, because of the higher complication rate, especially for major complications such as bowel burns. Recent multicentre studies comparing different methods give low rates for immediate morbidity and surgical complications (0.8 to 2.5 per cent of cases). Technical failure is rare but often due to a pre-existing condition, for example obesity or previous pelvic disease. Some failures are due, however, to difficulties with the instruments, especially at laparoscopy; here further developments and the use of teaching aids for those in training will help to reduce problems. Mortality from female sterilization is low, at 2 to 10 per 100 000 procedures; however, half is due in part to anaesthetic complications (hypoventilation), which can be avoided by intubation, and others are due to pre-existing medical conditions. Long-term follow-up has now shown that sterilization does not cause an increase in menstrual blood loss. Changes in blood loss during the first six months after operation reflect prior contraceptive use rather than the procedure. Referrals to hospital for gynaecological disease do not appear to be increased years after sterilization. Unfortunately, the failure rate for sterilization appears to be between 1 and 5 per 1000 procedures and is similar for male and female sterilization. Modern laparoscopic methods (clips and rings) have similar failure rates. This rate can, however, be decreased further. At present in 14 per cent of pregnancies following female sterilization the woman was pregnant at the time of operation (luteal phase pregnancy). Surgical error accounts for another 23 to 47 per cent; either the tube is not occluded properly or another structure is 'sterilized’. Thus it should be possible to reduce the present failure rate by 50 per cent with correct scheduling of operations and the use of a double-puncture laparoscope to increase the field of view and allow three-dimensional viewing. It is mandatory that all those in training should have a teacher and teaching aid when carrying out endoscopic procedures. The pregnancy rates are higher in the first year than later. Ectopic pregnancy ratios are increased and may occur later rather than earlier. Male sterilization does not appear to have long-term adverse effects; however, up to half may produce sperm-agglutinating or sperm-toxic antibodies. This may affect the chance of reversal. Morphological changes and hormonal changes following vasectomy are minimal. The majority of couples who accept sterilization find more enjoyment in marriage, and suffer no regret. Those being sterilized now are younger and have fewer children than ten years ago. In published series 1 per cent of men referred and 11 per cent of women have no desire for children and are sterilized before a pregnancy occurs. Reversal of sterilization is possible provided more than 5 cm of fallopian tube remains. Microsurgery increases the chance of pregnancy, though ectopics are increased. Male and female sterilization remains one of the most acceptable methods of contraception, being simple, safe and effective. However, being permanent couples will need information and time to reach a decision that sterilization is acceptable.