Acknowledgements Prof. Helen Duffy, Director of Human Rights in Practice and Gieskes Chair of International Humanitarian Law and Human Rights at the University of Leiden acted as lead consultant for the research and drafting of this publication. Furthermore, a number of experts have contributed in their personal capacity and provided input at various stages in the development of the document. They include: Kristian Bartholin (Deputy Head of Counter-Terrorism Division, Action against Crime Department, Council of Europe), Matthieu Birker (Adviser to the Council of Europe Commissioner for Human Rights), Dr. Berenice Boutin (Researcher in international law at the Asser Institute and Research Fellow at the International Centre for Counter-Terrorism – ICCT), Anne Charbord (Independent Researcher and Senior Legal Adviser of the former UN Special Rapporteur on the promotion and protection of human rights and fundamental freedoms while countering terrorism) René Elkerbout (former Judge from the Netherlands), Barbara Grabowska-Moroz (Programme Coordinator at the Helsinki Foundation for Human Rights, in Poland), Jonathan Horowitz (Senior Legal Officer, Open Society Justice Initiative), Dr. Sandra Krähenmann (Research Fellow at the Geneva Academy of International Humanitarian Law and Human Rights), Anastasia Miller (Director of Kostaniy Regional Office of the Kazakhstan International Bureau for Human Rights and Rule of Law), Dmitry Nurumov (Legal Programme Consultant at the International Commission of Jurists – ICJ), Róisín Pillay (Director of the Europe Regional Programme at the International Commission of Jurists – ICJ), Emir Prcanovic (Executive Director of the Association Vasa Prava, in Bosnia and Herzegovina), Matteo Sestito (Human Rights Officer at the UN Counter-Terrorism Executive Directorate – CTED), Letta Tayler (Senior Researcher on Terrorism/Counterterrorism at Human Rights Watch) as well as colleagues from the OSCE Secretariat’s Transnational Threats Department/Action Against Terrorism Unit (TNTD-ATU), Manuel Eising (Senior Legal Adviser) and Georgia Holmer (Senior Adviser on Anti-Terrorism Issues). 4 Guidelines for Addressing the Threats and Challenges of “Foreign Terrorist Fighters”