This paper presents further preliminary results of a trial of the prophylaxis of sepsis in 165 patients undergoing vascular surgery. The efficacy and safety of a single dose of teicoplanin was examined and compared with three doses of cephradine plus metronidazole. No significant differences were detected in the prophylactic efficacy in either group. The first interim report indicated abnormalities in liver function, maximum at 7 days, in both groups. These findings are confirmed in this second interim report. Raised levels of GGT and alkaline phosphatase are more prominent in patients receiving teicoplanin. Liver function improved by 28 days, however, suggesting that any abnormality is transient.