The concept of “translation” is required to carry a considerable load at several levels of inquiry. It functions as a causal element in sociological theories, and as a methodological tool, when used extensionally. Most importantly, it is the concept which in some way structures the field which we take as our object of inquiry. As such, it has particular functions in serving as a basis for generalizations and as a means of determining category membership. In response to what are perceived as difficulties in some of these areas, some scholars have hinted that the concept of “translation” might be fruitfully viewed as a prototype category. In this paper, the author reviews the philosophical and empirical arguments which support such a move, and outlines some of the programmatic consequences. The focus is on the resolution of current conceptual problems, and on the theoretical and metatheoretical implications.