Arms control thus far has essentially focused on the capabilities of the two superpowers, but an erroneous perception of each other's intentions may be equally dangerous. The Working Group on Nuclear Risk Reduction, co-chaired by Senators Sam Nunn and John Warner, has explored pragmatic and politically feasible means of reducing the risk of war. It recommends the establishment in Moscow and Washington of "nuclear risk reduction centers," and a variety of technical means to improve communications and exchange of information, including how both the U.S. and the U.S.S.R. might cope with nuclear terrorism and third-party dangers. This excellent book publishes the background papers written by well-selected experts. In a critical field not producing many fresh ideas, they do just that.