This chapter focuses on the indications for intrauterine insemination (IUI) in combination with mild ovarian hyperstimulation (MOH), its methods and risks. Optimal timing of the insemination is a crucial factor in IUI programs. After ovulation oocytes should be fertilized within several hours. Inseminated sperm (bypassing the cervix which acts as a reservoir for spermatozoa) has a limited period of survival, and sperm should therefore not be inseminated too early. When MOH is applied in IUI programs, one should strive after multifollicular growth of two to three dominant follicles to obtain the highest probability of conception with reasonable risks. When multiple pregnancies are kept to a minimum, MOH/IUI is more cost-effective compared with in vitro fertilization (IVF). Gonadotropins are the most effective drugs and should be offered in a low-dose, step-up protocol. Future randomized trials should investigate the cost-effectiveness of luteal support.