SummaryProspective studies compared (a) laparoscopic and open cholecystectomy and (b) laparoscopic and open appendectomy. A second purpose of this study was to assess the value of laparoscopic staging of pancreatic and liver tumors. A total of 141 cholecystectomy cases were studied, comprising a laparoscopic group (n = 50), an open prospective control group (n = 50), and historical controls (n = 41). The need for postoperative analgesics was significantly reduced with the laparoscopic procedure compared with open cholecystectomy. Hospital stay was 1 (1–5) day after laparoscopic cholecystectomy versus 6 (5–28) days after open cholecystectomy. Time away from work was 9 (4–21) versus 28 (21–60) days. These differences were statistically significant (p < 0.001). Complication rates were 8% in both prospective groups. A similar comparative study of laparoscopic appendectomy versus the open technique was undertaken, with 10 patients in each prospective group. Again, hospital stay and time away from work proved shorter for laparoscopic procedures. Finally, 15 staging procedures for pancreatic and liver cancers were per-formed. One patient with unresectable liver metastases was spared explorative laparotomy.