The aim of the study was to investigate: i) management and outcome of a representative patient cohort (n=9,991) with acute appendicitis enrolled in a prospective unicenter study through a time period of 27 years (middle Europe) & ii) the frequency & impact of specific categories (e.g., characteristics of the medical history, clinical & intraoperative findings, complications, relative risk factors of the disease) & iii) prognosis. Methods: By the mean of a prospective unicenter observational study, numerous characteristics (see “Aims”) were documented & influencing variables with significant impact on the outcome were statistically determined through 3 subsequent time periods. Results: 1) The wound abscess rate was 10.9 %. Perforation, surgical intervention on time, acute, gangrenous & chronic appendicitis, age, adverse diseases such as obesity, arterial hypertonus, diabetes mellitus, sex & missing intraoperative pathological finding showed a significant impact on the postoperative development of a wound abscess. 2) The longer the specific appendicitis-related medical history lasted, i) the more frequently a perforated appendicitis occurred (this rate significantly increased up to 13.1 % through the time periods), ii) the greater the false-positive appendectomy rate was (P<0.001) & iii) the higher the rate of required subsequent interventions was (4.3 %; P<0.001), which occurred significantly more often in obesity (6.5 %) & wound abscess (5.8 %). 3) The mean hospital stay was 11 days. 4) There was a significant decrease of the percentage of patients with no pathological finding of the “Appendix vermiformis“ intraoperatively, in particular through the last investigation period from 1997-2000 to only 6.8 % (1974-1985, 15.5 %; 1986-1996, 10.3 %). 5) The mortality was 0.6 % showing no significant difference between i) male & female patients (P=1.0), ii) the 3 investigation periods (P=0.077) & iii) the patients with false-positive appendectomy (0.4 %) & those with acute appendicitis (0.6 %; P=0.515). In summary, this prospective study demonstrated a substantial progress of the quality of surgical care with regard to the rates of false-positive appendectomies, of postoperative wound abscesses &, in particular, to mortality. Despite this, there was an increasing rate of perforated appendicitis in the investigated cohort. In conclusion, quality control remains an indispensable tool for the assessment of surgical care even in the most frequent diseases of daily practice, which can be further increased by i) a multicenter study setting in the future & ii) selected aspects investigated in randomized studies.