Dr. McCarroll received his Ph.D. in Psychology from the University of Arkansas in 1970 and his M.P.H. from the Harvard School of Public Health in 1978. He completed a U.S. Army internship in clinical/counseling psychology at Silas B. Hays Hospital, Fort Ord, California, 1978-79. From 1979 to 1982 he was the Chief of Mental Health at the U.S. Army Hospital, Berlin. He was the Assistant Chief of Psychology at the Walter Reed Army Medical Center from 1982 to 1988. In 1988, he joined the staff of the Department of Military Psychiatry, Walter Reed Army Institute of Research where he was Deputy Chief for Administration and also conducted a research program in the psychiatric effects of traumas and disasters with the Trauma Research Team in the Department of Psychiatry, Uniformed Services University of the Health Sciences. He retired from the Army in 1995 and joined the staff of this Department. He was the first author on over 25 original journal articles in the field of military medicine and the psychological effects of exposure to traumatic events. He has made over 30 presentations at scientific meetings. In addition, he has written book chapters, contributed to monographs, and made videotapes on these subjects.