These studies follow two earlier publications in the same series (noted in Foreign Affairs, Fall 1981). Plascov undertakes the difficult job of describing and interpreting, in short compass, what is happening and will happen as social change and the external environment have their impact on the traditional institutions of the individual Gulf states. A tour d'horizon rather than a tour deforce, this is a competent summary, stressing the elements of instability, although the precise nature of the trouble ahead defies prediction. Chubin, in dealing with the policies of the United States and the U.S.S.R., shows an appreciation both of the relevance of power to policy and of the limits of the military factor as a means of influence. Especially useful are his running accounts of the course of U.S. relations with Iran and Saudi Arabia and of Soviet relations with Iraq.