Objective To estimate the prevalence and morbidity of long-term catheterization (LTC) of the urinary bladder. Patients and methods A postal survey was conducted over two successive years from February 1989 to determine the incidence of LTC in three Bristol Health Districts with a total population of 827 595. During the first year the number of patients requiring emergency treatment for complications of LTC was also monitored over a 6-month period. In the second year, 54 patients were selected from the first survey and each was visited by one investigator every 2 weeks for 12 weeks to obtain information on catheter management, the incidence and type of complications, the attitudes of the patients or carers about the catheter and to assess the pH and microbiology of the patient's urine. Results The initial surveys identified 457 and 467 patients with long-term catheters during the 2 years, respectively; there were similar numbers of men and women in both years. The survey of catheter complications recorded 506 emergency referrals during the 6 months and the detailed study of 54 patients showed that 48% experienced catheter blockage, 37% reported urine by-passing the catheter and 30% noted haematuria. Patients found the catheter uncomfortable and depended on nursing support. Catheter blockage was associated with bladder stones, a high urinary pH and the presence of Proteus spp in the urine. Conclusion The prevalence and high morbidity of LTC cause a considerable demand on the available District and Hospital nursing services; most patients with long-term catheters are elderly, disabled or debilitated and more nurses need to be trained in the technique of catheterization and the management of the catheterized patient. Further research is required to reduce the morbidity of LTC by investigating measures to reduce catheter blockage and encrustation at the urine/biomaterial interface.