Gilman is from Hymera, Indiana and after graduating from Rose-Hulman Institute of Technology with a degree in Biological Engineering in 1974 he went to Indiana University School of Medicine and received his MD in 1978. Subsequent assignments include: He graduated from the Command and General Staff College and the Army War College. He is board certified in both Internal Medicine and Cardiovascular Diseases and is a fellow of the American College of Cardiology. He is married with three daughters.