The introduction of new protocols of immune suppression and especially the use of cyclosporine have led to a marked reduction of infective pathology in children receiving transplants. Nevertheless, infections still represent a major factor of morbidity and mortality in these patients. The above study lists the main viral infections, according to apparatus involved, that may arise, also with reference to the time elapsed since transplantation. The most up-to-date diagnostic possibilities for each infection are reviewed together with some indications on therapy which may subsequently be examined in greater detail.