Professor Sir Iain Chalmers practised as a clinician for seven years in the UK and the Gaza Strip, before becoming a full time health services researcher. Between 1978 and 1992 he was founding director of the National Perinatal Epidemiology Unit (www.npeu.ox.ac.uk). Between 1992 and 2002, he was founding director of the UK Cochrane Centre, which convened the meeting at which the Cochrane Collaboration (www.cochrane.org) was inaugurated. Since 2003, he has coordinated the James Lind Initiative to promote public and professional acknowledgement of the need to address uncertainties about the effects of treatments. He is coordinating editor of The James Lind Library (www.jameslindlibrary.org) and Testing Treatments Interactive (www.testingtreatments.org). He was knighted in 2000 for services to health care.