The authors present an accurate and comprehensive snapshot of appendicitis and the practice of appendectomy in the 1990s.Appendectomies were performed on 4950 patients in 147 Department of Defense hospitals worldwide over a 12-month period ending January 31, 1993.The median age was 23 years (range, 6 months to 82 years) with 64% males and 36% females. The patients were assigned a diagnosis of normal appendix in 632 (13%) cases, acute appendicitis in 3286 (66%) cases, and perforated appendicitis in 1032 (21%) cases. There were no differences in perforation and normal appendix rates between those operations performed in teaching hospitals versus community hospitals or between high-volume hospitals (> or = 100 appendectomies/year) versus low-volume hospitals. Both a preoperative temperature > or = 100.5 and a preoperative leukocyte count > or = 10,000 were incapable of discriminating between patients with appendicitis and those with a normal appendix. Multivariate analysis showed a significantly increased risk of perforation associated with age younger than or equal to 8 years (38% vs. 18%) and age older than or equal to 45 years (49% vs. 18%). Females had a significantly higher rate of normal appendices (19% vs. 9%) and a lower rate of perforation (18% vs. 23%). The complication rates to include reoperation and intraabdominal sepsis were markedly increased in those patients with perforation. There were four deaths in this series (0.08%).Despite a marked decline in associated mortality over the past 50 years, rates of perforation and negative appendectomy remain unchanged because they are influenced strongly by factors untouched by the intervening technologic advances.