Single dose cefotetan was compared with either a combination of metronidazole and cefazolin given for 24 hours or 3 doses of cefuroxime as prophylaxis in elective abdominal surgery. Wound infections and infections at remote sites (UTI and RTI) were similar in all groups. In a third group prophylaxis of abdominal surgery using a single 2g dose of cefotetan was compared to 2 doses of the same drug, given 12 hours apart. There was no demonstrable advantage to giving 2 doses. The low incidence of post-operative infections seen in all groups indicates the efficacy of cefotetan in the surgical prophylaxis of elective abdominal surgery.