Evaluation of a potential acute abdomen in patients who require intensive care for concurrent medical/surgical problems is often difficult due to ambiguities in the physical exam and ancillary diagnostic tests. Between August 1990, and February 1992, 25 ICU patients underwent diagnostic laparoscopy to evaluate a suspected acute intraabdominal process. Thirteen laparoscopies were negative, and 12 were positive. The overall accuracy for laparoscopy was 96% as confirmed by subsequent laparotomy, autopsy, or clinical course. Laparoscopic findings led to a change in management in nine patients (36%), leading to earlier exploration in four patients, and avoidance of laparotomy in five. No significant hemodynamic effects were noted during laparoscopy, and the procedure-related morbidity was low (8.0%). Diagnostic laparoscopy is a safe and accurate guide for managing the ICU patient with a suspected acute surgical abdomen. The use of laparoscopy can help avoid nontherapeutic laparotomy or confirm the need for operative intervention in these complex cases.