The United Nations Conference on Environment and Development (U.N.C.E.D.), widely known as the Earth Summit, convened in Rio de Janeiro, Brazil, from June 1 to June 12, 1992. It was the largest summit meeting of heads of state or government ever held. The Rio conference was concerned with environment and development. Participants at the Earth Summit adopted an “Earth Charter” or declaration of basic principles for the conduct of nations and peoples to achieve environmentally sound development. As his contribution to the Earth Summit, and also as an expression of his support of the goals of the conference, noted American painter Peter Max designed the Earth Summit stamps. Since the 1960s, Max has been known for his work on planetary causes. He is a passionate environmentalist and defender of human and animal rights. His signature will appear on the bottom of each sheet of stamps.