Up to 80% of women experience mood and physical symptoms associated with the menstrual cycle. This study assessed the impact of premenstrual symptomatology on functioning and treatment-seeking behavior for a community-based sample of women in the United States, United Kingdom, and France. A sample of 1045 menstruating women (aged 18-49) completed a telephone questionnaire that measured, at a point in time, premenstrual symptoms, impact on functioning, and treatment-seeking behavior. Results were generally consistent across the three countries. Irritability/anger, fatigue, and physical swelling/bloating, or weight gain were among the most commonly reported symptoms (approximately 80%). Functional impairment tended to be highest at home, followed by social, school, and occupational situations. Among working women, over 50% reported at least somewhat affected occupational functioning. Of women who ever missed work because of symptoms, 1-7 days were missed in the past year. Almost three fourths of the women had never sought treatment, and symptom severity was an important factor in treatment-seeking behavior. Treatment with selective serotonin reuptake inhibitors (SSRIs), which have demonstrated efficacy in this population, occurred with surprisingly low frequency. The functional impairment of premenstrual symptomatology (home, social, and occupational) and treatment-seeking behavior is consistent across countries. Women who experience more impairment are more likely to have severe symptoms and are more likely to believe, relative to women with less severe symptoms, that no treatment is available. This suggests significant unmet medical need in this more severely affected population. Improved clinical identification of these women and increasing awareness of the efficacy of SSRIs in treating premenstrual symptomatology may be of benefit.