We cannot be successful in leading our family, organization, or teams unless we first exercise SELF-DISCIPLINE. President Harry Truman said this, “In reading the lives of great men, I found that the first victory they won was over themselves, self-discipline with all of them came first.” Before we fight the battle in the world in and in the marketplace, we must win the war with ourselves. Here are six specific areas of our lives where leaders need to show self-discipline.