A companion volume to a four-part PBS series about US-Soviet relations, due to air later this year; by Bailer (Stalin's Successors, 1980; The Soviet Paradox, 1986) and Mandelbaum (director of the Project for East-West relations at the Council on Foreign Relations). The authors explore US-Soviet rivalry--particularly in the context of the recent prospects for peace and accommodation occasioned by the rise of Gorbachev--and find that the main basis for change in the Soviet Union lies in the ""exhaustion of the fundamental precepts of governance"" inherited from Stalin. Whatever reforms the Soviets undertake, however, will not, the authors believe, turn them into a Western-style democracy; but reforms should make the Soviet Union less forbidding and threatening in Western eyes. Contrasting the relative successes of the Soviet and American systems, Bialer and Mandelbaum believe that the successes of American allies, while often reducing American economic and power, at least advance the principles to which the US is committed--which is not the case for the Soviets: ""The relative American decline is, in a sense, a victory for liberal principles; the decline of the Soviet Union is a defeat for communist ones."" In general, the authors see prospects for further accommodations to depend heavily on the Soviets' willingness to concede changes in their policy vis-Ã -vis East Asia, the Third World, and Europe. Of all of these, they see a ""Finlandization"" of Poland to be the major Soviet step that would ease tensions between the two sides. As glasnost and perestroika enter the global lexicon, this useful commentary should interest the general reader as well as all those who labor in the complex vineyards of diplomacy.