Ovarian dysgenesis is the endstage of a process of follicular atresia, Turner syndrome (45,X) being the most common cause, with an incidence of 1 in 2500 female births. In addition to ovarian failure, these patients have short stature and a number of primary and derived somatic anomalies. Tertiary preventive measures are considered and treatment of short stature, estrogen deficiency and of infertility is discussed.