Abstract. The stable marriage problem (SM) and the Hospital / Residents problem (HR) are both stable matching problems. They consist of two sets of objects that need to be matched to each other; in SM men to women, and in HR residents to hospitals. Each set of objects expresses a ranked preference for the objects in the other set, in the form of a preference list. The problem is then to find a matching of one set to the other such that the matching is stable. We discuss issues concerning the creation of specialised constraints to solve these problems. We then present results that suggest that constraint programming is indeed a practical technology for solving these problems.