How can peace be encouraged and sustained in a violent world? For nearly half a century at the United Nations, ultimately as Under Secretary-General for Special Political Affairs, Brian Urquhart wrestled with this problem at its front lines. Managing the United Nations' peacekeeping operations in the world's hot spots-the Congo in the aftermath of Patrice Lumumba's assassination, Cyprus at the bloodiest moment of conflict between Greek and Turkish Cypriots, Kashmir, and, through the tragic cycle of four wars, the Middle East-he has tested the limits, and the possibilities, of peacekeeping in the modern world.