Perimenopausal depression affects a considerable number of women and is associated with significant disability and morbidity. Major and minor depressions are the two most prevalent forms of acute depressive illness. Major depression has an estimated lifetime prevalence of 17% and affects approximately twice as many women as men. While the relationship between the onset of depressive illness and reproductive senescence is controversial, epidemiological and clinic-based studies that have distinguished between the perimenopause and the postmenopause have documented that, for some middle-aged women, the perimenopause is associated with an increased vulnerability to depression. Future studies of perimenopausal depression should identify the number of women affected, individual risk factors and the role of hormonal therapies in this condition.