Both Frege and Husserl are well-known to have campaigned against a philosophical position known as psychologism. In this essay, I will begin by focusing upon the nature of psychologism in general, and then on the specific sort or sorts of psychologism Frege and Husserl were up against, before looking at the arguments they pressed against that position. Finally, I will ask if a radical anti-psychologistic position is a defensible one.