This introductory chapter argues that the governance and politics of migration is fundamental to both the form and plurality of migration and migrant experiences, and to the characteristics of politics, policy and governing. To illuminate this mutual significance, we highlight the theoretical importance of governance practices, political contestation, and the politics of knowledge, that combine to create an inter-disciplinary, critically informed approach to the study of migration governance and politics. By synthesising and applying these theoretical orientations, we further identify and examine three ‘constitutive contradictions’ that define how migration and migrants are governed, how and with what effects. First, that the governance and politics of migration are conceptually framed but can only be seen and understood in their material expression and transformation in ground-level practices of specific settings for specific migrants. Second that they have global and universal characteristics, but that governance practices are relational and particular in both form and effect. Third, that they are relatively stable arrangements that structure and constrain how governing is done, and yet migrant experiences and practices of mobility are always subject to dynamic change through action and contestation. In the third section, the chapter explains how the contributions to this volume reflect and explore these contradictions across the six dimensions through which migration governance and politics is imagined, enacted and contested: (1) conceptualisations; (2) the politics of categorising migration; (3) institution and regimes; (4) spaces of migration governance; (5) processes and practices; (6) contesting migration governance.