Mark Greaney is an author of best seling thrillers. His debut international thriller, The Gray Man, became a national bestseller and was nominated for a Barry Award in the Best Thriller category. The follow-up Gray Man thriller, On Target was also nominated for a Barry Award in the Best Thriller category. Ballistic, the third in the series also received glowing reviews including one from the New York Times. Mark is the #1 New York Times bestselling co-author of Threat Vector and Locked On by Tom Clancy with Mark Greaney, as well as the co-author of the upcoming release of Command Authority by Tom Clancy with Mark Greaney. Mark has a degree in International Relations and Political Science. In his research for The Gray Man novels he has traveled to more than fifteen countries, visited the Pentagon and many Washington, D.C. Intelligence agencies, and trained alongside military and law enforcement in the use of firearms, battlefield medicine, and close-range combative tactics.