The role of laparoscopic appendectomy remains controversial since many authors have suggested that overall morbidity is primarily a function of the degree of appendicitis rather than the operative approach. We have reviewed our appendectomy experience to determine the advantages and/or disadvantages of the laparoscopic technique in cases of acute appendicitis, and furthermore to ascertain whether the extent of disease should affect the surgical approach used. Data were accumulated for all 1158 patients who underwent appendectomy at a single institution during the following three time periods that span the pre- and postlaparoscopic eras: period I (1987 to 1990), period II (1991 to 1993), and period III (1994 to 1997). Cases were categorized with regard to pathologic findings and operative approach (i.e., open or laparoscopic appendectomy). The percentage of appendectomies performed laparoscopically increased with time (0%, 27%, and 79% for periods I, II, and III, respectively). Overall, the total operating room time was slightly shorter for laparoscopic compared to open appendectomy (99 vs. 102 minutes; P<0.05). Operating room times for open appendectomy remained unchanged, but the times for laparoscopic appendectomy decreased from period II to period III (119 to 94 minutes; P<0.001). In cases of gangrenous/perforated appendicitis, the times for laparoscopic appendectomy were significantly shorter than those for open appendectomy (98/115 vs. 120/125 minutes; P<0.001 for both). Overall, the hospital stay was shorter for patients undergoing laparoscopic appendectomy (1.63 vs. 4.21 days; P<0.001), and the difference was maintained in all three time periods. The differences in length of hospital stay for lap-aroscopic vs. open appendectomy were most dramatic in gangrenous/perforated cases (1.8/3.0 vs. 4.0/9.0 days; P<0.001), whereas there was only a slight difference in cases of simple appendicitis, for example, 1.6 vs. 2.1 days (laparoscopic vs. open appendectomy, period III). There was a significant decrease in the percentage of perforated cases in which surgical treatment had been delayed (>8 hours) (21%, 5%, and 5%) over the three time periods, but the rate of "negative" appendectomies was similar (10%, 8%, and 8%). The complication rates following laparoscopic and open appendectomies during period II were 5.4% and 7.5%, respectively (P>0.05). Laparoscopic appendectomy results in a marked decrease in the length of hospital stay and similar postoperative morbidity compared to open appendectomy. In cases of gangrenous or perforated appendicitis, laparoscopic appendectomy appears to be especially worthwhile in regard to both operating room time and hospital stay.