Larry Laudan's primary aim in his latest book, Science and Values, is to account for the high degree of agreement and the ubiquity of disagreement in science. Arguing that earlier philosophers have either concentrated on agreement and ignored disagreement or highlighted disagreement at the expense of agreement, he sets out to provide “a single, unified theory of rationality which promises to be able to explain both these striking features of science” (p. 3). However, while recognizing that Laudan has done much to clarify this issue and to bring traditional thinking about science into line with scientific practice, I shall argue that the basic problem remains to be solved. To do justice to agreement and disagreement, we must pursue a more radical course than the one Laudan charts.