Building and strengthening the rule of law in developing nations, countries in transition or emerging from armed conflict, is a central focus of UN work. As a result, there is a growing demand to better understand that delivery of justice in conflict and post-conflict situations and the impact of developments in this area. The United Nations Department of Peacekeeping Operations and the Office of the United Nations High Commissioner for Human Rights, in cooperation with other UN departments, agencies, funds and programmes, have developed an instrument to monitor changes in the performance and fundamental characteristics of criminal justice institutions in conflict and post-conflict situations, the UN Rule of Law Indicators. This Guide describes how to implement and measure these indicators. It provides step-by-step instructions on how to implement the instrument in a conflict or post-conflict setting. It is meant for first-time users as well as those with previous experience.