In 1985, faced with conflicts involving Iran and Iraq, the United Nations Security Council's permanent members joined forces for the first time to mobilize the U.N. against threats to international peace and security. Cameron R. Hume's authoritative account follows the transformation of the Security Council from a stage for acrimonious public diplomacy into a forum where governments collaborate to settle regional disputes. Hume underscores three interconnected themes: changes in Security Council diplomacy during forty-five years of successive conflicts involving Iran and Iraq (including Iraq's 1990 invasion of Kuwait); the Council's progression from invoking gentler means within its authority (under the U.N. Charter) to a more muscular assertion of its will; and the growing congruence between diplomacy as practiced in the Security Council and the bilateral policies of the major powers. Based on U.N. documents and the author's firsthand experience, The United Nations, Iran, and Iraq is important for students and practitioners in international organizations, multilateral diplomacy, and conflict resolution.