The sociology of science is dominated today by relativists who boldly argue that the content of science is not influenced by evidence from the empirical world but is instead socially constructed in the laboratory. Making Science is the first serious critique by a sociologist of the social constructivist position. Stephen Cole begins by making a distinction between two kinds of knowledge: the core, which consists of those contributions that have passed the test of evaluation and are universally accepted as true and important, and the research frontier, which is composed of all work in progress that is still under evaluation. Of the thousands of scientific contributions made each year, only a handful end up in the core. What distinguishes those that are successful? Agreeing with the constructivists, Cole argues that there exists no set of rules that enables scientists to certify the validity of frontier knowledge. This knowledge is "underdetermined" by the evidence, and therefore social factors-such as professional characteristics and intellectual authority-can and do play a crucial role in its evaluation. But Cole parts company with the constructivists when he asserts that it is impossible to understand which frontier knowledge wins a place in the core without first considering the cognitive characteristics of the contributions. He concludes that although the focus of scientific research, the rate of advance, and indeed the everyday making of science are influenced by social variables and processes, the content of the core of science is constrained by nature. In Making Science, Cole shows how social variables and cognitive variables interact in the evaluation of frontier knowledge.