General Colin Powell provides 18 lessons on leadership. Some key points include: being responsible sometimes means making difficult decisions that upset people; leaders must be accessible to problems from subordinates; don't blindly follow experts or get stuck in outdated ways of thinking; focus on attracting and developing talented people rather than organizational structure or titles; have optimism which inspires others; make decisions once you have 40-70% of information rather than waiting for 100%; put decision-making power in the hands of those doing the work rather than rear echelon analysts; and find people who work hard but also maintain balance and have fun. Ultimately, leadership requires making tough choices that can result in a lonely role.