The Marshall Plan has been heralded as one of the most important and successful foreign policies of this century. Historians generally agree that it was precisely the right medicine needed to heal wounds and restore confidence on both sides of the Atlantic following the destructive Second World War. It has also been credited with helping contain the spread of communism and providing the foundation for an enduring alliance that has produced years of peace in Europe. The Marshall Plan, however, has also been criticized as a selfish U.S. endeavor and a program that divided Europe. The purpose of this essay is to investigate the role of this widely acclaimed plan in U.S. post-war interests in Europe. It includes analyses of the plan's origins, goals, mechanics, and overall effectiveness. It also examines both the short and long-term economic, political and military significance of the Marshall Plan, including its relationship to the Truman Doctrine and containment policy. Finally, it focuses on how this historic plan helped further U.S. interests by forging a collective security mechanism and a strong economic political and military alliance network that has shaped Western Europe as it is known today.