We report two cases in which concurrent abdominal aortic aneurysm and colon carcinoma were treated in the same surgical procedure. In the first case both lesions were detected preoperatively but were uncomplicated. Single-stage treatment was undertaken electively. In the second case the colonic lesion was found during treatment of the aneurysm and both lesions were complicated. The decision to undertake single-stage treatment was made intraoperatively. Recovery was uneventful in both cases. Based on previous case reports and our experience in these two patients, we discuss the advantages and disadvantages of single-stage management. The principal risk is prosthetic infection. The advantages include avoidance of complications of the unoperated lesion and the ability to manage both lesions with only one operation. With a two-staged approach, complications following the first procedure and/or progression of the unoperated lesion may prohibit the second procedure. Despite the successful outcome in our patients, we recommend using single-stage management only in selected cases.