CMW/C/GC/3-CRC/C/GC/22 13. The Committees stress the primacy of the rights of the child in the context of international migration and therefore the need for the Conventions to be integrated by States into migration-related frameworks, policies, practices and/or other measures. 14. The Committees encourage States parties to ensure that the authorities responsible for children’s rights have a leading role, with clear decision-making power, on policies, practices and decisions that affect the rights of children in the context of international migration. Comprehensive child protection systems at the national and local levels should mainstream into their programmes the situation of all children in the context of international migration, including in countries of origin, transit, destination and return. In addition to the mandates of child protection bodies, authorities responsible for migration and other related policies that affect children’s rights should also systematically assess and address the impacts on and needs of children in the context of international migration at every stage of policymaking and implementation. 15. States parties should develop policies aimed at fulfilling the rights of all children in the context of international migration, in particular regarding migration management objectives or other administrative or political considerations. 16. States parties should develop a systematic rights-based policy on the collection and public dissemination of qualitative and quantitative data on all children in the context of international migration in order to inform a comprehensive policy aimed at the protection of their rights. Such data should be disaggregated by nationality, migration status, gender, age, ethnicity, disability and all other relevant statuses to monitor intersectional discrimination. The Committees stress the importance of developing indicators to measure the implementation of the rights of all children in the context of international migration, including through a human rights-based approach to data collection and analysis on the causes of unsafe migration of children and/or families. Such information should be available for all stakeholders, including children, in full respect of privacy rights and data protection standards. Civil society organizations and other concerned actors should be able to participate in the process of collecting and evaluating data. 17. Children’s personal data, in particular biometric data, should only be used for child protection purposes, with strict enforcement of appropriate rules on collection, use and retention of, and access to, data. The Committees urge due diligence regarding safeguards in the development and implementation of data systems, and in the sharing of data between authorities and/or countries. States parties should implement a “firewall” and prohibit the sharing and use for immigration enforcement of the personal data collected for other purposes, such as protection, remedy, civil registration and access to services. This is necessary to uphold data protection principles and protect the rights of the child, as stipulated in the Convention on the Rights of the Child. 18. The Committees are of the opinion that, in order to fulfil the rights of all children in the context of international migration, the following elements should be part of the policies and practices to be developed and implemented: (a) comprehensive, inter-institutional policies between child protection and welfare authorities and other key bodies, including on social protection, health, education, justice, migration and gender, and between regional, national and local governments; (b) adequate resources, including budgetary, aimed at ensuring effective implementation of policies and programmes; and (c) continuous and periodic training of child protection, migration and related officials on the rights of children, migrants and refugees and on statelessness, including intersectional discrimination. III. Fundamental principles of the Conventions with regard to the rights of children in the context of international migration 19. States parties to the Convention on the Rights of the Child have a duty to ensure that the principles and provisions therein are fully reflected and given legal effect in relevant domestic legislation, policies and practices (art. 4). In all actions concerning children, States should be guided by the overarching principles of non-discrimination (art. 2); the best 4