Episodes of candida infection at a teaching hospital were investigated. During a 3-year period from 1998 to 2000, there were 53 cases of candidaemia. Candida albicans (64.2 %) was the most common causative species, followed by Candida glabrata (17.0 %) and Candida parapsilosis (15.1 %). Molecular analysis of a cluster of eight infections from a single unit was performed using Southern blotting with Ca3 probe hybridization. This showed that the patients were each infected by unrelated strains of C. albicans. On occasion, isolates were found to be closely related within individual patients. Following Southern blot analysis, it was concluded that the infections were not part of an outbreak caused by a single, epidemic strain.