Surgery for acute cholecystitis has become the most frequent abdominal surgery in most hospitals, yet aspects of its management remain controversial. The aim of this study was to focus on the recent trends by demonstrating the principal differences between 2 series of patients operated on during 10-year intervals. Two hundred fifty-six consecutive operations for acute cholecystitis were performed from 1970 to 1977 (group O) and were compared to 260 cases operated from 1980 to 1987 (group N). Thirty-six variables were recorded in each case. All data obtained were computer recorded and analyzed. Several trends were observed in group N: 1. The population was significantly older with a higher proportion of males and diabetics. 2. There was a marked increase in common bile duct stones, acalculous cholecystitis, and gangrenous changes in the gallbladder. 3. There was a significant increase in patients operated on within 48 hours of admission. 4. There was a significant increase in the number of patients without previous history of biliary symptoms. 5. There was a significant decrease in the rate of wound infections and no statistically significant differences in mortality (N: 3.0%, O: 2.7%). 6. A decrease of the average postoperative hospital stay of 3.2 days was observed. In spite of the older and sicker population in group N, no significant increase in mortality occurred and the postoperative hospital stay was reduced.