On November 20, 1959, the United Nations General Assembly proclaimed a Declaration of the Rights of the Child, defining the ten basic principles listed in this 1980s poster. Many of these rights had already been mentioned in the Universal Declaration of Human Rights adopted by the General Assembly in 1948, and some had been addressed in the Geneva Declaration issued in 1924 by the League of Nations. However, it was agreed that the special needs of children justified a separate declaration. Human Rights Day, officially established on December 10, 1950, was set aside by the United Nations and its agencies to mark the anniversary of the adoption of the Declaration of the Rights of the Child. Posters like this one are published in the languages of the world and even in child-friendly versions to honor and promote the terms of the declaration; many incorporate all or some of the principles in list form, sometimes in simplified language or in easily comprehensible images. The poster was published by UNESCO, a special agency of the United Nations set up after World War II to promote international collaboration in education, science, and culture.