Most ovulatory women experience premenstrual symptoms (premenstrual syndrome, molimina) which indicate impending menstruation and are of little clinical relevance because they do not affect quality of life. A few women, however, experience significant physical and/or psychological symptoms before menstruation that, if left untreated, would result in deterioration in functioning and relationships. The precise etiology remains elusive, although new theories are gaining support in pre-clinical and early clinical trials. Refined diagnostic criteria allow better discrimination of this condition from other psychiatric diagnoses and the selection of symptom appropriate therapies that afford relief for most women. Pharmacotherapies (particularly selective serotonin reuptake inhibitors and SNRIs) represent the first-line treatment for premenstrual dysphoric disorder and severe, mood-related premenstrual syndrome. Continuous combined oral contraceptives have limited evidence for usefulness in premenstrual dysphoric disorder, whereas medical ovarian suppression is often recommended for patients who fail to respond or cannot tolerate first-line treatments (e.g., selective serotonin reuptake inhibitors). The use of cognitive behavioural therapies is promising, but it remains limited by sparse data and restricted access to trained professionals. A proper diagnosis (particularly the distinction from other underlying psychiatric conditions) is crucial for the implementation of effective therapy and alleviation of this impairing condition.