A striking feature of the last 20 years has been the proliferation of National Human Rights Institutions (NHRIs). Paradigmatic examples of such institutions include national human rights commissions and ombudsmen, particularly in new and developing democracies.  Mandated to protect and promote citizens’ human rights, NHRIs have been established in a wide range of legal and political systems.  The establishment of NHRIs in regions as diverse as the Asia-Pacific, Latin America and the Middle East forms part of a contemporary trend toward the diffusion of constitutional innovations across international boundaries and political regimes. International organisations as well as regional organisations, including the African Union, European Union, Organization of American States, and United Nations, have also played a pivotal role in supporting the creation of these state agencies as vehicles of collaboration with international and regional human rights bodies.