Given the prominent position Habermas' philosophy has gained, it is surprising that his method, rational reconstruction, has not caused more debate. This article clarifies what this method consists of, and shows how it is used in two of Habermas' research programs. The method is an interesting, but problematic way of confronting some of the basic epistemological questions in the social sciences. It represents an alternative to both the empirical-analytical and the hermeneutic tradition. On the basis of this methodology, Habermas' work (...) is situated between the transcendental and the empirical approach. A fundamental problem is that it remains unclear how to test the hypothesis put forward through rational reconstruction. (shrink)