Coagulase-negative Staphylococcus has emerged as a prominent pathogen in the neonatal intensive care unit and a recent report has implicated this organism in necrotizing enterocolitis (NEC). This same study suggests that Staphylococcus epidermidis is most commonly associated with a "mild form of enterocolitis." This prompted a review of the role of coagulase-negative Staphylococcus in the surgical complications of NEC. Between 1982 and 1986, 86 newborns underwent operation for perforation or intestinal necrosis secondary to NEC. Blood cultures, obtained within 72 hours of surgery, were positive in nine of 71 infants (13%). One third of these grew coagulase-negative Staphylococcus. Peritoneal cultures obtained at the time of operation were positive in 71 neonates. The incidence of Staphylococcus epidermidis was 30%. In a third of these cases, coagulase-negative Staphylococcus was the only organism covered. Overall mortality within the group was 33%. Coagulase-negative Staphylococcus was the single most frequent organism recovered from those infants who expired (35%). This data clearly indicates that Staphylococcus epidermidis must be considered as a significant pathogen in NEC. It is associated with both morbidity and mortality and, therefore, warrants appropriate aggressive therapy when recovered from the neonate with enterocolitis.