Paul Brennan, PhD, is the Head of the Genomic Epidemiology Branch of the International Agency for Research on Cancer (IARC/WHO), Lyon, France. The research focus of the branch is to use various genomic techniques and biomarkers to help identify non-genetic risk factors for cancer, and even help identify early stage cancers. His group works with colleagues in many different parts of the world, with active field work studies underway in central and eastern Europe, central and south-east Asia, and Latin America.