Alcohol clearly plays key roles in the promotion of cancers initiated by carcinogens. Thus, it is a major cause or significant contributing factor to many cancers. Ethanol affects the metabolism of anticancer drugs. It significantly contributes to viral hepatitis and liver cancer. In addition it modulates colorectal carcinogenesis, procarcinogen activation and risk of oral cancers. The mechanisms of ethanol's actions in carcinogen activation, and alcohol-related cancers are extensively reviewed. This book is designed for the researcher trying to understand how alcohol causes cancer, as well as the clinician/epidemiologist wishing to know more about its role in human cancer incidence.