Foreword I am very pleased to present the updated edition of Commissions of Inquiry and Fact-finding Missions on International Human Rights and Humanitarian Law: Guidance and Practice. This publication captures the experience of United Nations international commissions of inquiry and fact-finding missions, and the Office of the United Nations High Commissioner for Human Rights (OHCHR) in supporting them, over the past two decades. It presents the principles, policies, practices and methodologies that guide their work. International commissions of inquiry and fact-finding missions are now a key tool in the United Nations response to situations of violations of international human rights law and international humanitarian law, including international crimes. They are established with mounting frequency by the United Nations Security Council, the General Assembly, the Human Rights Council, the Secretary-General and the High Commissioner for Human Rights, to address violations in a growing variety of contexts. Regional organizations have also set up commissions and similar bodies. Commissions of inquiry and fact-finding missions have proved to be valuable in countering impunity by promoting accountability for such violations. They gather and verify information, create an historical record of events, and provide a basis for further investigations. They also recommend measures to redress violations, provide justice and reparation to victims, and hold perpetrators to account. They deserve to be fully supported, including by receiving the cooperation they require from States, and to be adequately resourced. The United Nations has acquired vast experience in this area. To date, my Office has supported the work of, or itself fielded, close to 50 international commissions of inquiry and fact-finding missions. My Office serves as the repository of institutional memory in this field and maintains a standing capacity to provide operational, legal, analytical and methodological support to these bodies. A degree of flexibility has helped commissions of inquiry and fact-finding missions to address a variety of situations. So while there is no single format for the constitution and functioning of all such bodies, the methodological tenets that guide all fact-finding and investigations on human rights and international humanitarian law, as developed based on relevant norms, standards and principles, provide a common thread across the various models, and ensure the production of sound analysis, reports and recommendations. The approaches outlined in this publication are well tested. The publication has also benefited from the feedback of members and staff of commissions and missions during GUIDANCE AND PRACTICE v