This paper raises two methodological questions from a philosophical perspective: (i) what is involved in a functionalist approach to law and (ii) what should be the focus of such an approach? To answer these questions, I will take two steps with both. To begin with, I argue that Pettit’s view on functionalist approaches may be made relevant for law; functionalist accounts target a virtual mechanism that explains why a system will be resilient under changes in either the system or its environment. Secondly, I make a distinction between two interpretations of his key-concept ‘resilience’, one in mechanical, the other in teleological terms. With regard to the second question I will take two steps as well. I argue why it does not make sense to ascribe wide functions to law, followed by a plea for a limited view on the function of law. This limited view is based on a teleological understanding of the law’s resilience. I argue that these two modes are interrelated in ways that are relevant for the interdisciplinary study of law.