The objective of this study was to determine the safety and efficacy of immediate laparoscopic cholecystectomy in the management of acute calculous cholecystitis. A prospective data collection was performed on all patients admitted to one surgical service over a 2-year period. The patients were managed by a uniform protocol consisting of (1) preoperative ERCP when common duct stones were suspected; (2) operation within 24 h of diagnosis; and (3) selective operative cholangiography. Previous surgery was not a contraindication to inclusion. The setting was an urban teaching hospital. There were 52 patients, 34 females and 18 males. Nineteen had undergone previous abdominal surgery. Five patients had preoperative ERCP and five had intraoperative cholangiography. The patients underwent laparoscopic cholecystectomy 0.8 +/- 0.4 days postadmission. Four (7.7%) were converted to open cholecystectomy. Fifty-eight percent had spillage of bile and/or stones. Patients went home 2.3 +/- 1.6 days postoperatively. There were no deaths and two complications: a subhepatic biloma and a superficial wound infection. Follow-up of all patients has revealed no late complications. We conclude: (1) Immediate laparoscopic cholecystectomy is safe and effective for acute cholecystitis even when complicated by previous surgery, inflammatory adhesions, and gangrene. (2) Intraoperative spillage of bile and stones does not lead to an increase in early complications. (3) Cholangiography is needed only when clinically indicated. (4) Laparoscopic cholecystectomy should be the treatment of choice for patients admitted for acute cholecystitis.