Interdisciplinary research centers are blooming in almost every university, and interdisciplinary research is expected to be a cure-all for the ills of academic science. Do disciplines still matter? To what extent are interdisciplinary problem-solving approaches driven by socioeconomic stakeholders and policymakers rather than by academics? And how is interdisciplinarity organized? Through an in-depth sociological study of the development of nanomedicine in France and in the United States – an area that combines nanotechnology and biomedical research – this book challenges two conventional views of interdisciplinary research and academic disciplines. First, disciplines do not merely form separate "siloes" which hinder the development of interdisciplinary research: rather, they are flexible entities whose evolution supports the long-term institutionalization of interdisciplinary science in French and US academia. Secondly, interdisciplinary research has no intrinsic virtue: its ability to respond to societal issues and advance knowledge depends on continued political support and long-term cooperation between stakeholders. Interdisciplinarity might also be threatened by oversold promises and struggles for recognition. A study of the many challenges facing the formation of creative and sustainable interdisciplinary scientific communities, The Policies and Politics of Interdisciplinary Research tackles vivid debates among academics and research managers and will appeal to scholars of sociology, science and technology studies and science policy.