Appendicitis is the first 3 years of life is uncommon and most cases are perforated at laparotomy. Case records at the Adelaide Children's Hospital were reviewed over a 12-year period. The findings were that acute appendicitis in this age group is commonly associated with respiratory symptoms and diarrhoea, the appendix was gangrenous or perforated in 92% of cases, and there was a significant delay in diagnosis. It is concluded that full evaluation of any child of this age with fever, vomiting, abdominal pain and tenderness is mandatory, and should include rectal examination, abdominal radiographs, differential white cell count and urinary examination. Examination under sedation may be necessary.