Infertility is defined as failure to achieve pregnancy during one year of frequent, unprotected intercourse. Evaluation generally begins after 12 months, but it can be initiated earlier if infertility is suspected based on history or if the female partner is older than 35 years. Major causes of infertility include male factors, ovarian dysfunction, tubal disease, endometriosis, and uterine or cervical factors. A careful history and physical examination of each partner can suggest a single or multifactorial etiology and can direct further investigation. Ovulation can be documented with a home urinary luteinizing hormone kit. Hysterosalpingography and pelvic ultrasonography can be used to screen for uterine and fallopian tube disease. Hysteroscopy and/or laparoscopy can be used if no abnormalities are found on initial screening. Women older than 35 years also may benefit from ovarian reserve testing of follicle-stimulating hormone and estradiol levels on day 3 of the menstrual cycle, the clomiphene citrate challenge test, or pelvic ultrasonography for antral follicle count to determine treatment options and the likelihood of success. Options for the treatment of male factor infertility include gonadotropin therapy, intrauterine insemination, or in vitro fertilization. Infertility attributed to ovulatory dysfunction often can be treated with oral ovulation-inducing agents in a primary care setting. Women with poor ovarian reserve have more success with oocyte donation. In certain cases, tubal disease may be treatable by surgical repair or by in vitro fertilization. Infertility attributed to endometriosis may be amenable to surgery, induction of ovulation with intrauterine insemination, or in vitro fertilization. Unexplained infertility may be managed with ovulation induction, intrauterine insemination, or both. The overall likelihood of successful pregnancy with treatment is nearly 50 percent.