This study is a retrospective analysis of 1472 adult patients undergoing bowel surgery in 31 US academic medical centers who were treated over a 4-month period. The purpose was to identify clinical factors possibly associated with the development of SSIs. The events of interest included not only superficial infections but also intra-abdominal infections and wound disruption. Some clinical criteria for diagnosis of SSI were objective (positive culture for organisms), but they were mostly subjective (wound exudates, surgeon's diagnosis, site reopened). Using subjective inclusion criteria among multiple institutions without prior standardization could be problematic. Similarly, there was no standardization in the choice of antibiotic used, use of heating devices, and technique of intraoperative temperature monitoring. The majority of operations were performed in open fashion, and two thirds were elective procedures. Only 12% of the wounds were classified as either contaminated or dirty. In terms of comorbidities, only 8% of patients were American Society of Anesthesiologists class 4 or higher, and those patients with conditions identified in previous studies to be associated with postoperative infection, such as obesity, renal failure, and diabetes mellitus, represented a very small fraction of the overall group.