The collapse of the Soviet Union, although providing a host of welcome opportunities for people of that nation, also exacerbated a number of transnational concerns just as serious as those that emanated from the bipolar hostility of the previous 50 years. Among these challenges is the marked increase in the theft of and illegal trafficking in nuclear materials, often referred to as nuclear smuggling.Prior to the early 1990s, nuclear smuggling generally involved small quantities of bogus materials or, at most, nuclear-associated materials that posed no serious danger to security. Recently, however, several disturbing incidents involving kilogram quantities of sensitive nuclear materials suitable for constructing bombs have occurred. No one doubts that hostile groups could conceivably bring weapons-usable nuclear material into the United States. Moreover, nuclear smuggling represents a possible shortcut for states such as Iran seeking plutonium or highly enriched uranium for their weapons program. The consequences of such states succeeding would be profound.The U. S. Government takes the threat of nuclear smuggling seriously. Congress has provided funds ad the Executive Branch has devised numerous successful programs targeted to reduce this danger at its source - but much more remains to be done. This book will contribute to filling that gap by providing a new tool, the nuclear smuggling pathway model, for addressing the nuclear smuggling phenomenon in a holistic way. This model is based on a general systems model and designed specifically as an analytical tool to assist national security personnel at all levels to understand, analyze, and prevent instances of illicit trafficking in nuclear materials. By offering a comprehensive approach usable by many different national and international agencies, the model may help counter a growing national security threat.Ervin J. RokkeLieutenant General, United States Air ForcePresident, National Defense University