This paper reports a survey of routine admission and preoperative diagnostic studies required by regulation at fifteen USAF hospitals. The results show that each hospital differs from the others on studies required. Clinical reports show that routine diagnostic studies are inappropriate on hospital admission. Clinical investigation has found that for preoperative patients a routine hemoglobin or hematocrit is indicated over age 60 years, an electrocardiogram over age 40 to 55, and a chest X-ray over age 60 to 70. The consensus of investigators is that diagnostic studies should be performed only when clinically indicated. Military hospitals could realize a substantial cost savings by not requiring unindicated diagnostic studies.