IN FASHIONING a colostomy one should consider the extent of serosa exposure; this should be kept at a minimum to prevent serositis. The complications of ileostomy are well known; its maturation was shown by Crile and Turnbull 1 to be completed when infection of the serosa subsides. Difficulties of the ileostomy stoma were lessened by covering the serosa with skin, as advocated by Dragstedt et al. , 2 and, better, by simply cutting the stoma off flush with the skin and sewing it, leaving no serosa exposed. As is attested by the relative paucity of complications from colostomy stomas, the serosa of the large bowel must be more resistant to infection than the serosa of the ileum; however, a similar maturation can take place, especially if a large amount of serosa is exposed for a prolonged time. Report of Cases The following cases illustrate serositis developing in colostomy stomas. Case