Seventeen university hospitals have joined their observations of septicemias through an informatics system. 461 septicemias have been collected in 1985. 407 are septic localizations, 299 primitives and 108 secondary. The frequent localisations are urologic (20.4%), pulmonary (20.15%), cutaneous (10.56%), abdominal (10.56%), cardiac and neurologic (9.58%). In 51.8%, the organisms are Gram positive cocci (Staphylococcus 23.9%, Streptococcus 27.9%). In 46.9% septic localizations are due to Gram negative bacilli with Escherichia coli (50.2%). The origin of septicemia is urologic (18%), abdominal (15.8%), cutaneous (8.7%), pulmonary (8.7%), stomatologic (7.2%), venous (4.3%). Gram positive cocci infections have more septic localizations than Gram negative bacilli infections. The mortality is more increased in pulmonary localizations (35%) than in the others localizations: venous (20%), cutaneous (19%), urologic (11%) and stomatologic (10%). Septic localizations which required the most of an antibiotics association are osseous (81.5%) and cardiac (80.5%), where as all septicemias require two antibiotics in 51%.