Intracytoplasmic sperm injection (ICSI) can now alleviate infertility in couples who could not conceive by other means. Most patients with obstructive azoospermia and some patients with non-obstructive azoospermia can now be treated. The practice of five years of ICSI (1991-1995) is reviewed in terms of patients selection and counselling, controlled ovarian stimulation and oocyte handling, semen evaluation and preparation, ICSI procedure, oocyte damage and pronuclear status after ICSI, embryo development, embryo transfer, freezing of supernumerary embryos, obstetrical outcome, prenatal diagnosis and follow-up study of the children resulting from ICSI.