APACHE II scoring was obtained retrospectively on patients admitted to the ICU of a university hospital for two consecutive years. During the first year the patients were treated by their attending physician (group 1); during the second year, by a trained critical care specialist in cooperation with the attending physician (group 2). There were 223 patients in group 1 and 216 in group 2. The mean APACHE II scores were equivalent (group 1, 19.0 +/- 9.1 vs group 2, 18.3 +/- 8.2, p = NS). ICU mortality was reduced by 52 percent (group 1, 27.8 percent mortality vs group 2, 13.4 percent mortality p less than 0.01) and overall hospital mortality was reduced 31.0 percent (group 1, 35.5 percent vs group 2, 24.5 percent, p less than 0.01). No increased significance in ICU or hospital mortality reduction could be shown between subgroups of patients with APACHE II scores of 0 to 14, 15 to 24, and greater than 25. This retrospective analysis suggests that a full-time, trained critical care specialist may have made a significant impact on the management of critically ill patients at our institution.