AIMS: A recent survey of UK general surgeons showed that almost 90% prefer to manage patients with acute cholecystitis by initial conservative management and delayed cholecystectomy (DC). The aim of this study was to assess the effectiveness of this management policy in a large university hospital. PATIENTS AND METHODS: All patients admitted with acute cholecystitis between January 1997 and June 1999 who went on to have a cholecystectomy were identified. Patients were required to have right upper quadrant pain for > 12 h, a raised white cell count and findings consistent with acute cholecystitis on ultrasound to be included in the study. RESULTS: 109 patients were admitted with acute cholecystitis (76 female, 33 male) with a median age of 62 years (range, 22-88 years). Conservative management failed in 16 patients (14.7%) who underwent emergency cholecystectomy due to continuing symptoms (9), empyema (4) and peritonitis (3). Symptoms settled in 93 patients and delayed cholecystectomy was performed without further problems in 66 (60.6%). 27 patients were re-admitted with further symptoms before their elective surgery and, of these, 3 were admitted for a third time before surgical intervention. Ten of the 30 re-admission episodes (33%) occurred within 3 weeks of discharge but 15 (56%) occurred more than 2 months after discharge. Elective surgery was undertaken at a median of 10 weeks post-discharge with 67% of operations occurring within 3 months. Mean total hospital stay (days) +/- SEM, for the three groups were: emergency surgery group, 10.21 +/- 0.85; uncomplicated DC group, 12.48 +/- 0.37; re-admitted group, 14.75 +/- 0.71. CONCLUSIONS: The policy of conservative management and DC was successful in 60.6% of cases but 14.7% of patients required emergency surgery and 24.8% were re-admitted prior to elective surgery with a resultant increase in total hospital stay. Performing elective surgery within 2 months of discharge in all cases would have reduced the re-admission rate by 56% and this along with the increased use of early cholecystectomy during the first admission are areas where the treatment of acute cholecystitis could be significantly improved.