In the opening chapters of Progress and Its Problems, Laudan presents a taxonomy of scientific accomplishments that has become very well-known among philosophers of science (Laudan 1977). I wish to point out some important omissions in this taxonomy and to recommend an alternative scheme. I believe that the distinctions I have drawn among scientific tasks are philosophically more interesting than Laudan’s. But I am not prepared to defend this opinion in detail. My chief claim is that the new taxonomy is (...) demonstrably closer to being exhaustive. So far as I know, it is exhaustive, although I would not be greatly surprised to discover oversights. A major benefit of Laudan’s scheme was that it called attention to conceptual (as opposed to empirical) activities in science which had frequently been left out of account in generalizations about the nature of scientific work. (shrink)