From October 1990 through March 1992, 1,310 patients underwent surgery on an out-patient basis. Fifty (3.82%) could not be released on the day of surgery, most often because of surgical complications (17), postoperative pain (11), poor screening (9), and nausea and vomiting (8). Screening for out-patient surgery must not be based solely surgical procedure. Factors of social context, personality and associated pathology must also be weighed.