It is unlikely that American officials will again face decisions exactly like those required of the Coalition Provisional Authority in spring 2003. Formal occupations had largely fallen out of favour by the second half of the twentieth century, and the CPA experience is not likely to be replicated. But it is certain that the international community will again find itself assisting societies emerging from conflict to build an enduring peace and establish a representative government. Learning how to best prepare for such a challenge is the key to more-successful future operations. In this regard, the occupation of Iraq provides an object lesson of the costs and consequences of attempting nation building without adequate preparation.