Thirty-eight patients colonized with multiply-resistant, plasmid-mediated, expanded-spectrum beta-lactamase (SHV-2) producing Klebsiella pneumoniae (MRK), were discharged from hospital to 22 nursing or residential homes during a hospital-based outbreak, in the Grampian region of north-east Scotland. MRK colonized the urinary tract in 74%, stool in 58%, respiratory tract in 29% and wounds in 11%. Mean length of colonization was 160 days (range 7-548). Mean length of stay in the homes after aquisition of MRK was 298 days. Compared with a control group of MRK-negative residents, MRK-positive residents had histories of more hospital admissions, underlying disease and complete immobility. Evaluation of these homes showed high standards of care and good facilities. Despite prolonged carriage of MRK by the index cases there was no evidence of spread to the other 886 residents who were screened, and there was evidence of only minor environmental contamination. Given the available evidence, patients colonized with MRK can be accommodated in good-quality nursing and residential homes, on discharge from hospital, with little fear of spread to other residents.