Hundreds of researchers have made significant contributions to cognitive science. What follows is a set of short academic biographies of people whom we believe should be counted on anyone's list of important contributors; the work of many of them is discussed in the Companion. Not every important figure is included; and some people are included, especially from the history of cognitive science, who would not describe, or could not have described, themselves as cognitive scientists despite their considerable impact on the field. We trust that the list will be useful to students doing research in cognitive science and to readers who wish to familiarize themselves with the work of specific contributors.