Notwithstanding the significant progress made in our understanding of polycystic ovary syndrome (PCOS), the field remains ripe for further discovery and more intensive translational research. Immediate priorities include developing evidence-based criteria for diagnosing PCOS and for assessing the response to the various treatments available. The basis for the identification of PCOS remains mainly expert opinion, and the lack of universally accepted evidence-based criteria limits the generalizability of research studies on PCOS. Additional important areas requiring intensive investigation include the natural history and etiology and the long-term sequelae and prevention of the disorder. Overall, this disorder is a prototype for the benefits of translational science and a transdisciplinary approach to understanding the pathophysiology and therapy for anovulatory infertility. © 2006 Elsevier Ltd. All rights reserved.