Infection at the pin tract is a common complication of external fixation. This study was done to compare the rate of pin site infection following combined 1% silver sulphadiazine and 5 % chlorbexidine dressing with 5% chlorhexidine dressing alone.This was a prospective controlled study which compared the results of pin site dressing using a combination of chlorhexidine and silver sulphadiazine cream (Study group) with dressing using chlorhexidine alone. Eligible patients had external fixation in the treatment of open fractures or orthopaedic conditions. Pin-tract infection was deemed to be present iferythema, cellulitis or purulent discharge occurred around a pin site. We did not distinguish between deep and superficial infection.The study group had one hundred and seventy pin sites while the control group had one hundred and sixty-four pin sites. Thirty-eight patients, in whom thirty-seven uniplanar external fixators and one Ilizarov ring fixator were used, made up both groups. Three patients (7.9%) had pin tract infection in the study group while nine patients (23.7%) had pin tract infection in the control group.There was a significantly lower prevalence of pin-tract infection amongst patients whose external fixation pins were dressed with 1% silver sulphadiazine and 5% chlorhexidine than in those dressed with chlorhexidine alone (P = 0.03). Therefore, we advocate the use of a combination of silver sulphadiazine and chlorhexidine for pin site dressing.