This article sets out to establish the extent to which changes in the institutional structure of Soviet security and defence policy influenced Soviet military-strategic policy in the 1980s. Institutional structure is defined as the nature of civil-military relations, which is measured along two dimensions: the degree of leadership control over the military, and the interrelationship between civilian and military participation in security and defence policy. Hypotheses are formulated which connect the nature of civil-military relations to military-strategic decisions as well as to their conversion into concrete measures. The empirical analysis of three decisions shows that the Soviet leaders sought to create a more defensive strategy by increasing centralized control over agenda-setting, policy design and decision-making. It did so by expanding the community of experts in military-strategic policy and reducing military participation in foreign and, to a lesser extent, arms control policy. It failed to institutionalize civilian participation and monitoring of the implementation of military-strategic decisions, apparently because it had a top-down perspective on the policy process. The general conclusion is that institutional change at the input side of the policy process is easier to establish than at the output side.