Disorders (differences) of sexual development encompass a variety of conditions with atypical development of chromosomal, gonadal, or anatomic sex. Three of the most common differences of sex development conditions include congenital adrenal hyperplasia, complete androgen insensitivity, and Turner syndrome. Obstetrician–gynecologists who care for affected individuals in their practice must be familiar with the genetic, endocrine, and anatomic considerations of the most common conditions to provide optimal care. As women with these conditions transition to adult care, the gynecologist needs to assess the patient's understanding and educate her regarding her diagnosis and ongoing medical care. All of these conditions may affect self-perception, mental health, fertility, sexual function, and bone and cardiovascular health. Women with congenital adrenal hyperplasia need lifelong endocrine management and require genetic counseling before pregnancy. Women with androgen insensitivity syndrome require counseling regarding gonadectomy and hormone replacement therapy and may require vaginal elongation for intercourse. Most women with Turner syndrome experience premature ovarian insufficiency and require long-term estrogen replacement. Women with Turner syndrome often have congenital anomalies and autoimmune disorders, which require regular monitoring and care during adulthood. The purpose of this review is to provide the obstetrician–gynecologist who cares for adult women with the most common disorders (differences) of sexual development conditions an outline of the current recommendations for screening and ongoing health care with particular emphasis on the underlying genetics, management of subfertility, infertility and sexual concerns, approach to hypogonadism, and understanding of associated comorbidities.