Very early in our studies on the gallbladder it became clear to my associates and me that the present systems of classification of cholecystitis were at fault. As the work progressed it became with increasing frequency impossible to correlate the pathologic changes with either the clinical, bacteriologic or the postoperative course. As increasing numbers of cases became available for study, these discordances were so glaringly evident that it was clear that our methods of pathologic classification were inadequate (figs. 1 and 2). For these reasons the various conditions were entirely reclassified de novo, as will be elucidated in the comment. MATERIAL AND METHOD The material studied consisted of a series of fifty-four specimens which were removed at operation in cases in which elaborate chemical and pathologic studies as well as chemical studies had been made, as reported in a recent paper.1In sixty-one other cases, chemical, bacteriologic and clinical