This paper brings the diagnosis and treatment of this interesting yet infrequent condition to contemporary standards through an assessment of past literature and a re-evaluation of the problem in view of technological advances. Two cases of annular pancreas are cited with a review of the last 183 years of literature. Only 100 cases, however, were reported in enough detail to examine outcomes in general and to arrive at a reasonable conclusion in terms of recommendations for diagnosis and operative intervention in adult annular pancreas. Two observations are brought to light. Despite all present diagnostic tools including endoscopic retrograde cholangiopancreatography diagnosis at best is made in only 60 per cent of patients preoperatively. Intraoperative expertise remains the best diagnostic modality available to date. Enteroenterostomy seems to be the intervention of choice for a multitude of anatomic and physiologic reasons and with a wide array of surgical options available when additional factors need to be addressed.