William Fraser is recognized internationally as a leading perinatal clinical trialist whose research on obstetrical labour has led to changes in practice that benefit women and their newborns. He contributed to the development of national and international research networks that collaborate to address important obstetrical questions through large simple trials. He has acted as a leader in the broader obstetrical academic community through his role in the Association of Professors of Obstetrics and Gynecology which, along with CIHR, sponsors the National Training programme in Research in the Reproductive Health Sciences that he leads.