This special issue focusses on how migration and diversity researchers experience and perform their role as academic experts in politicised public debates about migration and diversity. In a world wherein experts are increasingly demanded for policy development and wherein migration as well as ethnic, racial and religious diversity are among the themes dividing voters the most, migration and diversity researchers find themselves in a challenging position. How do they view their obligation to participate in public debate and how does their identities as researchers relate to such participation? This special issue will discuss the impact and implications of these challenges in the Scandinavian context, although the theme of researchers’ roles in politicised public debate is of a broader relevance both to other geographical regions and to other controversial research fields. Debates on public sociology, on the science/media interface, and on present challenges to academic expertise more generally, are central to the discussion.