Methodology 19. The overall focus of and main issues to be addressed by the Handbook were formulated after desk research and consultations with relevant United Nations entities, agencies and stakeholders. Subsequently, an expert meeting was held in New York in April 2018. Legal scholars, child rights practitioners, civil society organizations, United Nations agencies and think tanks participated in the meeting. They identified key international legal frameworks concerning the issues of focus. The experts were also consulted throughout the development of the Handbook, providing comments to the drafts. 20. The outcome of the April 2018 expert meeting was shared and discussed at consultative meetings with government officials at the regional level. For this purpose, the United Nations Counter-Terrorism Centre organized three consultative meetings in South-East Asia (July 2018), Europe (September 2018) and the Middle-East and North Africa (January 2019). The participants at the regional consultative meetings shared national practices and legislative frameworks. Some of the good practices and challenges shared in these meetings are included in the Handbook. In April 2019, another expert meeting was held in New York to review the draft Handbook and develop key recommendations. Terminology A child 21. The Handbook follows the definition of “a child” under the Convention on the Rights of the Child as “every human being below the age of 18 years unless, under the law applicable to the child, majority is attained earlier”.33 The Convention on the Rights of the Child has near universal status. Many of 33 Convention on the Rights of the Child (1989), art. 1. 18. its provisions are now also part of “customary international law” that binds all States, even if they have not ratified the Convention. Under the Convention, all persons under the age of 18 are entitled to special protection.34 Of particular significance to children affected by the foreign fighter phenomenon is that the Optional Protocol to the Convention on the involvement of children in armed conflict prohibits armed groups from recruiting anybody under 18.35 Foreign terrorist fighters/foreign fighters 22. The Security Council has defined “foreign terrorist fighters” as those “who travel or attempt to travel to a State other than their States of residence or nationality, and other individuals who travel or attempt to travel from their territories to a State other than their States of residence or nationality, for the purpose of the perpetration, planning, or preparation of, or participation in, terrorist acts, or the providing or receiving of terrorist training”.36 23. Concerns have been raised over the labelling of individuals, as well as their families, by association, as foreign terrorist fighters, difficulties related to the criminal regulation of individuals’ intentions, and the blurring of lines between terrorism and armed conflict, with consequences for human rights protection and the protection regime under international humanitarian law. There are 34 Committee on the Rights of the Child, general comment No. 4 (2003) on adolescent health and development in the context of the Convention, para. 1. The Committee emphasizes that “adolescents up to 18 years old are holders of all the rights enshrined in the Convention; they are entitled to special protection measures, and, according to their evolving capacities, they can progressively exercise their rights (art. 5)”. 35 Optional Protocol to the Convention on the Rights of the Child on the involvement of children in armed conflict (2000), art. 4(1); Use of children under the age of 15 in hostilities is also a war crime. Rome Statute of the International Criminal Court (1998), art. 8(2)(b)(xxvi). 36 Security Council resolution 2178 (2014), para. 6(a).