Humanitarian aid workers belonging to United Nations organisations, PVOs / NGOs or the Red Cross / Red Crescent have traditionally enjoyed both international legal protection, and de facto immunity from attack by belligerent parties. However, attacks on humanitarian workers have occasionally occurred, and became more frequent since the 1990s and 2000s. In 2012 there were 167 incidents of major violence against aid workers and in 2013 there were 474 attacks. This is attributed to a number of factors, including the increasing number of humanitarian workers deployed, the increasingly unstable environments in which they work, and the erosion of the perception of neutrality and independence. In 2012, road travel was seen to be most dangerous and kidnappings of aid workers have quadrupled in the decade with more aid workers victims of kidnapping that any other form of attack. ICRC promotes a framework for Neutral Independent Humanitarian Action (NIHA) to enable differentiated role understanding.
The legal basis for protection of humanitarian workers in armed conflicts is contained in the Geneva Conventions of 1949 and the related and of 1977. These treaties describe the category of civilians and outline the rights and obligations of non-combatants during armed conflicts. These rights include the right to be treated humanely; to have access to food, water, shelter, medical treatment, and communications; to be free from violence to life and person, hostage taking, and humiliating or degrading treatment; and the prohibition against collective punishment or imprisonment. Non-combatants include citizens and nationals of countries that are not party to the conflict.
While the Geneva Conventions guarantee protection for humanitarian workers, they do not guarantee access of humanitarian workers to affected areas: governments or occupying forces may, if they wish, ban a relief agency from working in their area. Médecins Sans Frontières was created in 1971 with the express purpose of ignoring this restriction, by providing assistance to populations affected by the Biafran civil war despite the prohibitions of the government of Nigeria.