Postoperative morbidity after colorectal surgery was retrospectively investigated, comparing 32 alcoholics (greater than or equal to 60 gm of alcohol a day) to 32 controls (less than 25 gm of alcohol a day). The material originated from 260 male patients and the two groups were paired with respect to operative procedure, diagnosis, age-complicating cardiopulmonary diseases, weight, and smoking habits. Postoperative morbidity was higher (P less than .01) in the alcohol group (59 percent with major complications, 75 percent with major and minor complications) compared with the control group (19 percent with major, 33 percent with major and minor). The alcoholics also stayed longer in the hospital (26 days vs. 17 days) (P greater than .01). This apparent increased surgical risk in alcoholics is reevaluated in prospective investigations.