Polycystic ovary syndrome (PCOS) is a complex heterogeneous endocrine disorder, occurring due to synergistic interaction of genetic, epigenetic, and environmental factors, associated with both reproductive and metabolic abnormalities resulting in short-and longterm consequences on the women\\'s health. Anovulatory disorders account for about 30–40% of female infertility, with PCOS accounting for 80–90% of World Health Organization (WHO) group 2, normogonadotropic normoestrogenic anovulation (hypothalamic-pituitaryovarian dysfunction). It is now well-recognized that PCOS is not necessarily a disease [earlier known as polycystic ovarian disease (PCOD)], but rather a cluster of features that may predispose to various diseases in different stages of life, such as anovulatory infertility, type 2 diabetes mellitus and metabolic syndrome. This chapter reviews the diagnostic criteria, etiopathophysiology, clinical manifestations, evaluation, management in adolescents, women of reproductive age, pregnancy and menopause, and the long-term sequelae of this disorder.