Polycystic ovary syndrome remains a mystery with respect to its aetiology, consequences and management. There is an increasing emphasis on its familial origins although the genes involved are unknown. There are significant changes in risk profiles for cardiovascular disease but no clear clinical evidence of morbidity or mortality. There is evidence of improvement in insulin resistance or insulin sensitivity drugs but uncertainty about improvement in pregnancy outcomes. This review looks at the latest advances in understanding polycystic ovary syndrome, particularly in obesity.