The role of the colostomy in the definitive correction of anorectal malformations is controversial with regard no only to indications for its use, but also to location and type. We reviewed the records of 272 patients with 307 colostomies and analyzed the frequency of complications related to these controversial points. There were 250 completely divided and 57 loop colostomies, constructed in either the sigmoid or transverse colon. Twenty-five colostomies were associated with complications that included retraction, stenosis, dehiscence, prolapse, infection, bowel obstruction, sepsis, and death. Twelve additional colostomies were placed in positions that impeded the definitive correction of the malformation: 9 sigmoidostomies were too distal and 3 were located in the right-upper abdominal quadrant and did not permit pull-through without tension. Colostomy prolapse and pull-through infection were statistically less likely with a completely diverting colostomy. Thirty-five patients with rectovestibular malformations were encountered in this series. Ten were referred from other institutions after attempted repair without a colostomy and all 10 had complications of infection, dehiscence, retraction, and reopening of the fistula. In contrast, there were no complications in the remaining 25, in whom the repair was preceded by a colostomy, nor after re-repair of the other 10. These findings support the need for a colostomy prior to the repair of this malformation. We recommend a carefully constructed, high, completely diverting sigmoid colostomy prior to the initial definitive repair of anorectal malformations. A right transverse colostomy is preferable preceding redo operations.