Graham Cookson is chief executive of OHE, the world's oldest independent health-economics research organisation, with deep connections to the healthcare industry, academia and governments. An econometrician by training, he focuses on health-system efficiency, policy evaluation, and pricing and reimbursement in pharmaceutical markets. Through OHE's Change Initiative, Professor Cookson leads pioneering research programmes on prevention and US drug pricing policy. He is best known for his work on the economics of staffing and skill mix in the NHS in England, which was critical to the development of the NICE Guidelines on Safe Staffing.