Information management in large multicenter studies requires a specialized approach. The Estudo Longitudinal da Saúde do Adulto (ELSA-BrasilBrazilian Longitudinal Study for Adult Health) has created a Datacenter to enter and manage its data system. The aim of this paper is to describe the steps involved, including the information entry, transmission and management methods. A web system was developed in order to allow, in a safe and confi dential way, online data entry, checking and editing, as well as the incorporation of data collected on paper. Additionally, a Picture Archiving and Communication System was implemented and customized for echocardiography and retinography. It stores the images received from the Investigation Centers and makes them available at the Reading Centers. Finally, data extraction and cleaning processes were developed to create databases in formats that enable analyses in multiple statistical packages. In 2001, Guimarães et al 7 described that some areas of scientific activity in epidemiology, like that of chronic non-communicable diseases, were still not well developed in Brazil. In the last decade, as a result of a substantial increase in the promotion of health research, these diseases have begun to be better investigated. The comprehensiveness of the collected information has been expanded and the methodology for its acquisition has become more complex. DESCRIPTORS: Multicenter Studies as