This article investigates changes over time in the substitutability of paralegals for other employees within the law firm. The substitutability between paralegals and associate lawyers does not seem to have increased over time; if anything, the increased role for paralegals has been accompanied by increased specialization of tasks performed. In fact, in the largest legal markets and the legal practices employing the most specialized attorneys, paralegals and associates appear to be complementary inputs. In contrast, there is some evidence that secretarial and clerical workers have become more substitutable for professional workers in the law firm.