Studies of exposures in the workplace have made major contributions to our understanding of human carcinogenesis. In the International Agency for Research on Cancer (IARC) Monographs on the Evaluation of Carcinogenic Risks to Humans, occupational exposures account for 31 per cent of the factors classified with "sufficient" evidence for human carcinogenicity, for 42 per cent of those listed as "probable" human carcinogens, and 42 per cent of those listed as "possible" human carcinogens. Given the prominent role played by occupational exposures in our understanding of human carcinogenesis, it is worthwhile to take stock of where we are regarding studies of occupational cancer. In this presentation, Dr. Aaron Blair will look at how successful research has been in reducing the burden of cancer, and what we should be doing in the future. Dr. Blair is the interim director of the new Occupational Cancer Research Centre, the first of its kind in Canada. Prior to this role, he was the chief of the Occupational and Environmental Epidemiology Branch of the U.S. National Institutes of Health’s National Cancer Institute. He remains scientist emeritus at the U.S. National Institutes of Health.