A total of 88 patients with haematological malignancies who required Hickman catheters for intensive chemotherapy, were randomized to receive either a single bolus intravenous injection of teicoplanin, or no teicoplanin, immediately before insertion of a double lumen Hickman catheter. There was a lower incidence of catheter-related Gram-positive sepsis in patients receiving prophylactic teicoplanin. This benefit was particularly clear in patients who were already neutropenic at the time of catheter insertion. Prophylactic teicoplanin may, therefore, be useful as a routine procedure during the insertion of Hickman catheters for this group of patients.