One of the three international SPS standard-setting organizations that is recognized by the World Trade Organization (WTO), the IPPC is the worldwide authority for development ofplant health standards, guidelines, and recommendations (e.g., to prevent transfer of a plant disease from one country to another). The treaty establishing the IPPC was signed in 1952. IPPC standards are set (and enforced) via regional SPS institutions such as the North American Plant Protection Organization (NAPPO), European Plant Protection Organization (EPPO), etc.