The Charlson-Age Comorbidity Index (CACI) is a validated tool used to predict patient outcome based on comorbid medical conditions. We wanted to determine if the CACI would predict morbidity and mortality outcomes in patients undergoing surgery for colorectal carcinoma. Records of 279 consecutive colorectal cancer patients who underwent laparotomy by a single surgical group between 1997 and 2001 were reviewed in a retrospective fashion for patient demographics, stage at diagnosis, operation, surgeon, perioperative complications, tumor characteristics, comorbid diseases, performance status, length of stay (LOS), disposition, and mortality. Using the preoperative history and physical, all patients were assigned a score for the CACI. Perioperative morbidity and mortality were recorded and graded to account for severity. The University Statistical Consulting Center and SPSS software were used to analyze the results. The patients were primarily white (97.1%) with a male-to-female ratio of 1:1.2 and a median age of 72 years. AJCC stage at presentation was stage 0 (3.2%), stage I (28.3%), stage II (24.4%), stage III (24.4%), or stage IV (19.7%). Median LOS was 7.0 days. Perioperative mortality was 17 of 279 (6.1%), and overall mortality was 32.6% at a median follow-up of 18.5 months. Higher CACI scores and AJCC stage at presentation correlated with longer LOS and overall mortality. Only the CACI correlated with perioperative mortality and disposition. No correlation was observed with location of tumor, type of surgery, or surgeon. Patients with higher cumulative number of weighted comorbid conditions as indicated by the CACI are at higher risk for perioperative and overall mortality. This simple scoring system is also a significant predictor of disposition (home versus extended care facility) and LOS. The CACI can be a useful preoperative tool to assess and counsel patients undergoing surgery for colorectal carcinoma.