In recent years it has become increasingly fashionable for both lawyers and political scientists to emphasize the interdisciplinary character of their work. Yet, all too often the promise of interdisciplinarity is not kept. Rather, interdisciplinarity is confused either with the crude instrumentalization of other disciplines' knowledge while ignoring the underlying methodological assumptions or with an oversimplified dissolution of disciplinary distinctions. What is frequently missing is threefold: on a general level, reflection on the potential gains and the potential risks or obstacles related to the collaboration of the two disciplines; on a more concrete level, a conscious awareness of complementary or compatible concepts and approaches; and finally, on the most concrete level, the identification of specific topics for which interdisciplinary cooperation is particularly advantageous. Taking these considerations seriously, this paper first draws on the field of migration research to illustrate the benefits deriving from the cooperative effort between legal and political science in that area. Secondly, on a more general level, this paper identifies some potentials as well as some pitfalls of the interdisciplinary cooperation between law and politics.