A former Marine shares 9 tricks to become mentally tough

U.S. Department of Agriculture/Flickr You can read every leadership book out there, until you're an expert in the art of managing other people. But ultimately, this knowledge is useless if you don't know how to manage yourself. That's according to Andrew D. Wittman, author of "Ground Zero Leadership: CEO of You." (The book is available through Wittman's website, but not on Amazon.) Wittman is a former US Marine, police officer, and federal agent; today he trains organizations and individuals on ...