EPIC-Italy is the Italian section of a larger project known as EPIC (European Prospective Investigation into Cancer and Nutrition), a prospective study on diet and cancer carried out in 10 European countries. In the period 1993-1998, EPIC-Italy completed the recruitment of 47,749 volunteers (15,171 men, 32,578 women, aged 35-65 years) in 4 different areas covered by cancer registries: Varese (12,083 volunteers) and Turin (10,604) in the Northern part of the country; Florence (13,597) and Ragusa (6,403) in Central and Southern Italy, respectively. An associate center in Naples enrolled 5,062 women. Detailed information for each individual volunteer about diet and life-style habits, anthropometric measurements and a blood sample was collected, after signing an informed consent form. A food frequency questionnaire specifically developed for the Italian dietary pattern was tested in a pilot phase. A computerized data base with the dietary and life-style information of each participant was completed. Blood samples were processed in the same day of collection, aliquoted (RBC, WBC, serum and plasma) and stored in liquid nitrogen containers. Follow-up procedures were validated and implemented for the identification of newly diagnosed cancer cases. Cancer incidence was related to dietary habits and biochemical markers of food consumption and individual susceptibility in order to test the role of diet-related exposure in the etiology of cancer and its interaction with other environmental or genetic determinants. The comparability of information in a prospective study design is much higher than in other studies. The availability of such a large biological bank linked to individual data on dietary and life-style exposures also provides the unique opportunity of evaluating the role of selected genotypes involved in the metabolism of chemical compounds and DNA repair, potentially related to the risk of cancer, in residents of geographic areas of Italy characterized by specific cancer risk and different dietary patterns. Baseline characteristics of participants are briefly described.