Foreword Terrorism poses multi-dimensional challenges and requires multi-dimensional responses. Experience has shown that respecting and protecting human rights and fundamental rule of law principles are not an impediment to, but a vital condition for addressing security threats effectively. The threats posed by so-called “foreign terrorist fighters” (FTFs) and the responses required to address those threats are no exception. Human rights and the rule of law provide a solid framework for effective action to address the potential threats and challenges posed by individuals who travel for terrorism-related purposes. United Nations Security Council (UNSC) Resolutions 2170 (2014) and 2178 (2014), adopted under Chapter VII of the UN Charter, determined that the flow of FTFs constitutes an “international threat to peace and security”. As a result, the resolutions oblige states to take wide-reaching measures to prevent and suppress this flow.1 Recalling the UNSC resolutions, the 2014 OSCE Ministerial Council in Basel noted that the threat of FTFs may affect all regions and states, even those far from the conflict zones to which FTFs are travelling.2 Since then, the challenges have changed in several ways due to new trends in the return and relocation of FTFs from conflict zones in Iraq and Syria. UNSC Resolution 2396 (2017), sought to address those new challenges.3 What has not changed is the need for human rights and rule of law-based approaches with respect to all aspects of the flow of FTFs in countries of departure, transit, destination and relocation. A flurry of legislation, policies and practices has unfolded around the globe in an effort to address the issue. But the breadth of the term FTF and the wide-reaching responses taken by states raise multiple questions concerning their compliance with, and the implications for, the rule of law and the international human rights framework in countering terrorism. States have committed themselves to combatting the potential threats and challenges posed by FTFs within the framework of international law, in accordance with their obligations under international human rights law and international humanitarian law. The UNSC resolutions, the OSCE Ministerial Declaration on FTFs and other regional initiatives, all consistently reflect and confirm this commitment. 1  See: Preamble of UNSC Resolution 2178 (2014), adopted on 24 September 2014, UN Doc. S/RES/2178 (2014), (hereafter, UNSC Resolution 2178 (2014)). The resolution was preceded by UNSC Resolution 2170 (2014), which called upon states to suppress the flow of FTFs to the Islamic State in Iraq and the Levant (ISIL) and Al Nusrah Front (ANF) and all other entities associated with Al-Qaida, and to bring the FTFs of those groups to justice. See: UNSC Resolution 2170 (2014), adopted on 15 August 2014, UN Doc. S/RES/2170 (2014), para 8. 2  Preamble of the “Declaration on the OSCE Role in Countering the Phenomenon of Foreign Terrorist Fighters in the Context of the Implementation of UN Security Council Resolutions 2170 (2014) and 2178 (2014)”, adopted by the OSCE Ministerial Council in Basel on 5 December 2014, MC.DOC/5/14 (hereafter, OSCE Ministerial Declaration on FTFs). 3  UNSC Resolution 2396 (2017), adopted on 21 December 2017, UN Doc. S/RES/2396. 6 Guidelines for Addressing the Threats and Challenges of “Foreign Terrorist Fighters”