Today, health and medical achievements have brought life expectancy at birth from 47 years of 1900 to almost 80 in 2000. Despite this, there are significant differences within the population in terms of quality of life, health, access to healthcare services and assistance received. Even worse differences lie between the developed and developing countries. Even these last differences are only apparently distant from our world, in fact they are closely related to us because of the intense migration flows. All this adds up to the usual problems related to the study and control of environmental contamination (water, food, atmospheric air, indoor air, work environment); to the fight against the ancient and new infectious agents; to control of the social and health consequences of chronic-degenerative pathologies; to the new ways of producing and using food, the need to address the challenge of new ways of organizing and managing health services, consistent with budget constraints with the need to ensure efficiency, effectiveness of health interventions. The main objective of the Department is to offer the academic world and civil society a response to these problems and a center of study and control of all the factors that can affect the individual and collective health of the people. To achieve this goal, knowledge is needed from different professional and specialized skills, better developed and operating in multidisciplinary integrated model. The Department of Public Health and Infectious Diseases "G. Sanarelli" is thus an instrument that combines research and didactic-training activities related to epidemiology, prevention, planning and organization of health services.