Arms control agreements are often celebrated as triumphs of cooperation over competition in order to achieve mutually beneficial outcomes. This assumption places significant emphasis on absolute security for all states despite the fact that security gains created by arms control agreements are not equally distributed between participants (as states possess diverse military capabilities, national security interests, etc.) and states are ultimately more concerned about relative security versus adversaries. How do states leverage this unequal distribution for their own benefit? This article develops a theoretical framework that describes how states use arms control as a mechanism to achieve relative military advantage over adversaries (i.e. cooperative means to achieve competitive ends) and is tested against two major arms control agreements between the United States and the Soviet Union, the INF Treaty and START I. These findings have policy implications as great power states grapple with the role arms control will play in an increasingly-multipolar international system.