Amenorrhea in younger women is a fairly common problem encountered both by general practitioners, gynaecologists and school doctors. The spectrum of its causes is very broad. Fortunately, the disease is most frequently due to functional disturbances, which present no immediate threat to the patient and give the doctor time for thorough evaluation and symptomatic therapy. There are cases, however, urging prompt diagnosis and sprcific treatment to prevent irreversible damage. Every doctor should be aware of these relatively uncommon, yet serious cases of amenorrhea. He/she should be familiar with the associated signs and symptoms, as well as the most rational diagnostic approach, enabling those patients to be diagnosed and treated appropriately and in time.