Objectives-This report presents 2006 national estimates and selected trend data on the use of nonfederal short-stay hospitals in the United States. Estimates are provided by selected patient and hospital characteristics, diagnoses, and surgical and nonsurgical procedures performed. Estimates of diagnoses and procedures are presented according to the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Methods-The estimates are based on data collected through the National Hospital Discharge Survey (NHDS). The survey has been conducted annually since 1965. In 2006, data were collected for approximately 376,000 discharges. Of the 478 eligible nonfederal short-stay hospitals in the sample, 438 (92 percent) responded to the survey. Results-An estimated 34.9 million inpatients were discharged from nonfederal short-stay hospitals in 2006. These discharges used 166.3 million days of care and had an average length of stay of 4.8 days. In 2006, hospitals with under 100 beds accounted for 77 percent of inpatient discharges in nonmetropolitan areas, but only 13 percent of inpatient discharges in metropolitan areas. Forty-three percent of the total days of care were accounted for by persons age 65 and over, although this age group represented only 12 percent of the population. The rate of discharges with a first-listed diagnosis of stroke among persons age 65-74, 75-84, and 85 and over dropped significantly from 1996 to 2006. The leading diagnostic category was diseases of the circulatory system. Among the 8.7 million inpatient discharges age 45-64, 4.2 million (48 percent) had at least one surgical procedure.