There have been increasing reports worldwide of vancomycin resistant enterococci (VRE) since they were first noted over ten years ago. This study sought to investigate the clinical significance of VRE in Ireland and to compare the phenotypic, genotypic and molecular characteristics of isolates recovered from patients in different institutions. The relative contribution of inter-hospital transmission of strains to the dissemination of VRE in Ireland was assessed. Hospital surveillance for VRE is not well established in Ireland. The organism has been detected in seven hospitals. Detection has been predominantly in oncology inpatients in large tertiary referral hospitals in the Dublin metropolitan area in whom strains generally represent asymptomatic gastrointestinal tract colonization. The predominant species is E. faecium with the Van A resistance phenotype. Twenty-seven (87) of 31 isolates from one unit were shown to be of the same or closely related strain as were 10 (63%) of 16 from another unit, indicating significant nosocomial transmission within institutions. There was no evidence for inter-hospital transmission of VRE. VRE is established in Ireland and nosocomial transmission readily occurs. Regular surveillance for VRE is indicated in high-risk populations in large institutions, specific risk factors for the acquisition of VRE need to be defined and optimal control and preventative strategies need to he instituted to detect and preempt the spread of this organism.