This article discusses how images and perceptions shaped by the Cold War led to misunderstandings on both sides of U.S.-Soviet biomedical exchanges. The article explores these misunderstandings and shows that their origins are to be found in the Cold War interactions between the two superpowers. The Cold War was more than just a structural constraint on the two sides' interactions. Political tensions between the superpowers interfered in the process of scientific cooperation, and the geopolitics of the period imbued science with political significance, but the crucial thing was the way the Cold War framed cooperation in the sphere of biomedicine. When exchange participants were interpreting and responding to interactions with their foreign colleagues, the analytical framework they used was the Cold War. Their adoption of this framework posed a barrier to achieving mutual understanding not only of the other side's motives or intentions but of the science itself. The exchange participants came away with a distorted picture of the structure and function of each other's research enterprise.