Ovulation induction is the principal infertility treatment for women with polycystic ovarian syndrome (PCOS). Among PCOS patients who are overweight or obese, weight loss is the most physiologic method of inducing ovulation. For women in whom weight loss is not possible, or for lean women with PCOS, clomiphene citrate is an effective first-line method of ovulation induction. In clomiphene-resistant women, alternative treatments include adjunctive metformin or dexamethasone, aromatase inhibitors, or ovarian drilling. If there is no pregnancy despite several cycles of successful ovulation induction, gonadotropin treatment should be considered, in which case in vitro fertilization is recommended as the safest and most effective strategy.