Summary1The history of appendicitis mortality prior to 1933 is briefly reviewed.2Mortality statistics for appendicitis in Australia from 1933 to 1957 are presented, both for the population as a whole, and for the various age groups. A remarkable reduction in mortality rates is in evidence.3Possible reasons for the improving prognosis are advanced. These possibilities ar.e examined in the light of two series of appendicitis cases from the Royal Adelaide Hospital (Series A from 1936‐8, Series B from 1956‐7). Antibiotics, intestinal decompression and intravenous infusions appear to have been the main factors contributing to the improved prognosis. This improvement has occurred principally in the group of perforative‐appendicitis.4The graver prognosis of appendicitis in the aged is shown; and factors responsible for this are summarized. This older group remains a challenge for further improvement.5Post‐operative complications in the Royal Adelaide Hospital Series are r