To support co-operative work among health professionals and institutions it is necessary to share healthcare information about patients in a meaningful way. But, nowadays, in most hospitals health data are distributed across several information systems whose interconnection is difficult to achieve, this leads to the so-called islands of information. This paper briefly describes the architecture, design and implementation of the PANGEA system. PANGEA allows healthcare professionals to access patient information stored in heterogeneous autonomous information systems through a set of formal aggregates of health data based on the European pre-standard of Healthcare