Colonel David H. Hackworth served in the military for twenty-five years and received 110 medals for his service. He is the author of About Face, Hazardous Duty, The Price of Honor, and Steel My Soldiers' Hearts. He died in 2005.
Jocko Willink is author of Extreme Ownership, a decorated retired Navy SEAL officer, and cofounder of Echelon Front, where he is a leadership instructor, speaker, and executive coach. Jocko spent twenty years in the US Navy SEAL Teams, starting as an enlisted SEAL and rising through the ranks to become a SEAL officer. Jocko returned from Iraq to serve as Officer-in-Charge of training for all West Coast SEAL Teams. During his career, Jocko was awarded the Silver Star, the Bronze Star, and numerous other personal and unit awards. In 2010, Jocko retired from the Navy and launched Echelon Front where he teaches the leadership principles he learned on the battlefield. Jocko is also the author of the children's book Way of the Warrior Kid and the New York Times bestseller Discipline Equals Freedom.