Long a source of contention and ambiguity in Washington, the US Institute of Peace (USIP) is seen by some as a vital part of the US national security apparatus, by others as a counter to the influence of militarism in US foreign policy, and by still others as an example of fiscal irresponsibility and bureaucratic redundancy-when it is noticed at all. Michael English traces the history of USIP to determine why and how it came into existence, how its mission has changed over time, its successes and its failures, and how it has come to take the shape that it has today.