Numerous, but heterogeneous studies have been performed about premenstrual syndrome, with finally a lack of credibility and interest among practitioners. More recently with the diagnosis criteria generalization, psychiatrists were more concerned about this syndrome, because of anxiety and mood symptoms involved in social impairment and need of medical care. In 1983 in the United States, the National Institute of Mental Health conference devoted to this topic proposed the first diagnosis criteria, requiring a prospective and daily assessment of the symptoms. In 1987, the American Psychiatric Association, in the DSM III-R, introduced the Late Luteal Phase Dysphoric Disorder diagnosis that became in 1994 in the DSM IV the Premenstrual Dysphoric Disorder, with the same diagnosis criteria. In the literature, prevalence rates are very heterogeneous according to the diagnosis criteria used and to the populations studied. One of the most relevant criteria is the induced impairment, such as avoidance of social activities, or search for medical care. Lifetime prevalence is thus estimated between 75 and 85% if considering the report of one or several symptoms, between 10 and 15% in case of medical care request, and between 2 and 5% in case of social activities interruption. To distinguish isolated complaints from a disabling disorder, self-questionnaires are the best way of assessment in a so complex and changing disease. Most of the epidemiological studies found a positive correlation between the premenstrual dysphoric symptoms and the lifetime major depressive disorder diagnosis. However, recent prospective studies failed to find an association between premenstrual syndrome and an increased risk of major depression. On the other hand, some studies showed that the premenstrual period is a risk period for associated psychiatric disorders exacerbations, as the obsessive-compulsive disorder, more severe alcohol intakes in case of alcoholism, symptoms increase in schizophrenics, or higher rates of suicide attempts. The most widely studied and frequently blamed etiopathogenic hypothesis is the serotonin dysregulation. Serotonin is particularly involved in expression of irritability and anger, but also in occurrence of depressive symptoms and specific food cravings, precisely found in the premenstrual dysphoric disorder. Among their different effects, estrogens increase the density of serotonin receptors and enhance the sensitivity to serotonin agonists. Moreover, some studies found a significantly different response to d-fenfluramine, a serotonin agonist, in women with premenstrual dysphoric disorder. In psychoanalytical theories the premenstrual syndrome was associated to a "femininity complex", to an ambivalent pregnancy desire, and to unconscious conflicts relating to sexual preference. In this context, Karen Horney, who took a great interest in the premenstrual period, was radically opposed to the Freudian theory of feminine sexuality, in particular the negation of the female sex. For Karen Homey, the "desire of penis" is more expressive of the woman's spite not to share the sexual, but also political, social and cultural benefits fallen to men. To understand the premenstrual period feelings it is also necessary to take into account the personal history of the woman and the psychosocial factors involved, as the social and cultural beliefs, and the mother-daughter communication. Medical cares are necessary when symptoms constitute a severe and disabling disorder. Among non-psychiatric treatments, progesterone was the most widely prescribed treatment, but relating to recent performed studies, it failed to prove its efficiency in such an indication. In the same way, the efficiency of the contraceptive pill was not demonstrated. The most prescribed psychiatric treatments are serotonin re-uptake inhibitors and benzodiazepines. First studies showing serotonin re-uptake inhibitors efficiency in premenstrual dysphoric disorder were performed in the beginning of the nineties, with clomipramine and fluoxetine, and later fluvoxamine, paroxetine, sertraline and citalopram. Studies having compared the efficiency of antidepressants according to their serotonin activity (paroxetine or sertraline versus maprotiline, that is a selective noradrenaline re-uptake inhibitor), showed that serotonin re-uptake inhibitors were significantly more efficient on all symptoms than maprotiline, that was not more efficient than placebo. Low doses of clomipramine (10 to 50 mg per day) seem to be sufficient and it appears also preferable to prescribe an intermittent treatment because of a possible tolerance effect, susceptible to be warned by phases free of treatment. Alprazolam was the most studied benzodiazepine in this indication. Most studies were positive, using daily posologies of 0.25 to 4 mg during the 6 days preceding the menses, with improvement of irritability, anxiety and depressive mood. The general practitioner frequently carries out psychological support, in particular in case of mild symptoms without consequences. Nevertheless, underestimate a more severe psychological suffering is a risk, firstly because there is no systematic interrelationship between the somatic symptoms intensity and the psychological distress, and secondly because premenstrual period is a special emotionally moment to put in evidence psychological or relational disruption. All kinds of psychotherapy can be relevant, even though the training of relaxation techniques is particularly suitable in such an indication. In conclusion, and in spite of the generalization of the diagnosis criteria in the international psychiatric classifications as the DSM, the premenstrual syndrome remains a complex and polymorphous disorder. The premenstrual syndrome was considered for a long time like a somatic disease, but now the psychiatric symptoms severity justifies most often the medical cares. In order to distinguish some isolated and mild complaints, of a disabling disorder, the standardized prospective auto-assessment is the most relevant method. Finally, intermittent prescription of serotonin re-uptake inhibitors appears to be the most effective treatment, the previously used hormonal treatments not having made proof of their efficiency in such an indication.