A work of fundamental importance, by the Director of the International Institute for Strategic Studies, which should be carefully read by all those seriously concerned with arms control and East-West relations. Bertram raises disturbing questions about the future feasibility of arms control because of the impact of technological change on the ability to develop quantitative restrictions on levels of forces; the difficulty in verifying qualitative restraints; and the multi-mission role of many new weapons, which undermines traditional categories of negotiation. Doubt is cast on whether technological change can be controlled by such often-favored means as limits on testing or the curtailment of procurement. Unilaterally adopted restraints, while useful, are not capable of replacing negotiated agreements. Instead, Bertram suggests a new arms control approach based upon explicitly restraining military missions-such as the ability to destroy vulnerable land-based ICBMs or threatening second-strike, missile-firing nuclear submarines. This criterion-of missions rather than weapons-is, in fact, more a changed emphasis than a radical departure from current practice, for it still depends upon quantitative restrictions for implementation. And, of course, it would have to be acceptable to the Soviets. Yet this imaginative and carefully reasoned study merits wide debate as one new set of ideas for dealing with the increasing difficulties in maintaining a credible strategic balance.