Eighty-two episodes of bacteremia due to streptococci (including the genus Enterococcus) in 78 patients hospitalized at Institut Jules Bordet between 1986 and 1988 were reviewed. The incidence ranged from 5.5 to 7.6 per 1,000 admissions (16% of all bacteremias). Enterococcus faecalis, Streptococcus sanguis, and Streptococcus mitis were the most prevalent isolates, followed by Streptococcus angionosus, Streptococcus salivarius, and large colony-forming beta-hemolytic species (A, B, C, and G). Twenty-one episodes were polymicrobial. One-half of the patients had solid tumors, and one-half had hematologic malignancies. Forty-two patients were neutropenic (less than 1,000 polymorphonuclear neutrophils/microL). Only 15 episodes were acquired outside the hospital, and 11 episodes were breakthrough bacteremias. Twenty patients died within 1 month of the onset of streptococcal bacteremia. Five patients, two of whom were neutropenic, had fatal adult respiratory distress syndrome. The source of bacteremia remained undetermined in 35.4% of the episodes; the oral mucous membrane and the gastrointestinal tract were the most frequently recognized associated sites of infection. No unexpected antimicrobial resistance was observed except in two penicillin-resistant strains, one S. mitis and one E. faecium. No relation between peak or trough serum bactericidal titers and outcome could be demonstrated.