Valerie studied medicine at Sydney University, Australia. After a few years of clinical work in Australia, New Guinea and the UK, she spent almost 20 years at the London School of Hygiene & Tropical Medicine working in the Department of Epidemiology. In 1988 she became the Director of the Cancer Epidemiology Unit in Oxford. Major focuses of her research include the role of reproductive, hormonal and infectious agents in cancer. She is Principal Investigator for the Million Women Study and leads the international collaborations on breast, ovarian and endometrial cancer. She is President of the International Epidemiological Association.