The idea for this volume came out of a desire to assess the trajectory of critical thinking in the study of world politics. We saw critical theory as having reached an impasse, after the highly successful period in which its popularity surged – almost to the point of becoming ‘mainstream’ or common sense in some parts of the academic world. We the editors are part of a generation of researchers for whom the word ‘critical’ has become, to a great extent, a household name. The proliferation of ‘critical approaches’ led us to ask a number of questions. Does it still make sense to use the ‘critical’ label to designate an approach or methodology? Is there an emerging ‘critical orthodoxy’? What has the critical literature achieved? Where has it failed or remained silent? What are its limits and challenges? How can critical thinking be pushed forward? Finally, what has happened to ‘traditional’ (‘uncritical’) thinking? We set out to provide a fresh perspective upon the ‘critical turn’ in International Relations and Security Studies – one that would revisit its origins, celebrate its eclecticism, consider its limitations and open doors to future developments.