We find all degrees of menstrual pain. It may be so mild as to be little more than discomfort, or so intense that unconsciousness results. The pain may be sharp and knife-like, or it may be a dull ache. It may be localized, low down in one or both sides, distributed over the whole abdomen or concentrated in the back. With this pain, there may be headache, or a headache may be the only symptom. Frequently there is gastro-intestinal disturbance--nausea, vomiting, diarrhoea, or constipation. In anaemic cases fainting is common. Local or operative treatment is not as a rule necessary, for the majority of cases yield to a strict regime of hygienic living. The regime should include regulation of sleeping, of eating, of hours of work and relaxation, of dressing and of exercise. The exercise should be prescribed and directed by a person trained in medical gymnastics. Frequently mental disturbances are associated with the phenomenon of menstruation. The most usual symptoms are heightened irritability, hysterical manifestations and depression. Depression is often the only symptom; to some girls the premonitory "blues" signify the approach of the period. Occasionally we encounter the reverse, an excessive stimulation and feeling of well-being and strength. There is some loss in the power of concentration. In normal cases, however, this loss is less than many people suppose it to be. Lassitude and a feeling of general debility are confined chiefly to the anaemic cases. The mental symptoms clear up as the physical condition is improved, aided by a sensible attitude toward the whole process. Often girls who suffer some pain live through the whole month in dread of the period. This attitude should be changed, by lessening the pain and by psychic therapy. Psychic therapy has proved successful in obstinate cases.