Liver cancer affects about one million people per year worldwide, being the second leading cause of cancer mortality. The incidence of its two main types, hepatocellular carcinoma (HCC), followed by intrahepatic cholangiocarcinoma (ICC), is one of the few common cancers with increasing mortality rates in most regions of the world. The study of LC etiology, mechanisms and strategies for prevention remains therefore a global priority, though it is often neglected in terms of research and development efforts in North America and Europe. The main challenge for HCC is to understand the role of nutritional and metabolic factors in cancers not related to hepatitis B (HBV) and C virus (HCV) infection, and their interaction with HBV and/or HCV; the etiology of ICC is still largely unexplained. Various consortia of epidemiological studies have been established during the last two decades, to pool and analyze data on risk factors for various cancers, which have produced important novel results, but no such effort has yet been proposed for LC.