After training in internal medicine, nephrology and epidemiology Dave Sackett’s first career (age 32) was as the founding Chair of Clinical Epidemiology & Biostatistics at McMaster. In his second career he began to design, execute, interpret, monitor, write and teach about randomized clinical trials, an activity that continues to the present, some 200 trials later. His third career was dedicated to developing and disseminating “critical appraisal” strategies for busy clinicians , and ended when he decided he was out of date clinically and returned (at age 49) to a two-year “retreading” residency in Hospitalist Internal Medicine. His fifth career (and the only one he didn’t enjoy) was as Physician-in-Chief at Chedoke-McMaster Hospitals. His sixth career was as Head of the Division of General Internal Medicine for Hamilton and Attending Physician at the Henderson General Hospital. When a chair was created for him at Oxford, he took up his seventh career as foundation Director of the NHS R&D Centre for Evidence-Based Medicine, Consultant on the Medical Service at the John Radcliffe Hospital, Foundation Chair of the Cochrane Collaboration Steering Group, and Foundation Co-Editor of Evidence-Based Medicine. Retired from clinical practice at age 65, he began his eighth career by returning to Canada and setting up the Trout Research & Education Centre, where he reads, researches, writes and teaches about randomized clinical trials. Along the way, he has published 10 books, chapters for about 50 others, and about 300 papers in medical and scientific journals.