the Marshall Plan. Since 1949, it has been headquartered in the Château de la Muette in Paris, France. Succeeding the Marshall Plan, the OEEC became focused on economic issues. In the 1950s, the OEEC provided the framework for negotiations aimed at determining conditions for setting up a European Free Trade Area, to bring the European Economic Community of the Inner Six and the other OEEC members together on a multilateral basis. In 1958, a European Nuclear Energy Agency was set up under the OEEC. By the end of the 1950s, with the job of rebuilding Europe effectively complete, some leading countries felt that the OEEC had outlived its purpose but could be adapted to fulfil a more global mission, which proved to be a cumbersome task. Following several (occasionally unruly) meetings at the Hotel Majestic in Paris, which began in January 1960, a resolution was reached to create a body that would not only solve European and Atlantic economic issues, but also devise policies that could assist less developed countries. This reconstituted organisation would bring the US and Canada, who were already OEEC observers, on board as full members, and the OEEC would set to work straight away on convincing Japan to join the organisation. Founding Following the 1957 Rome Treaties to launch the European Economic Community, the Convention on the Organisation for Economic Co-operation and Development was brought together to reform the OEEC. The Convention was signed in December 1960, and the OECD officially superseded the OEEC in September 1961, consisting of the European founder countries of the OEEC, with the additions of the United States and Canada. Three countries, (Netherlands, Luxembourg, and Italy)—all OEEC members—ratified the OECD Convention after September 1961, but are nevertheless considered founding members. The official founding members are: Austria Belgium Canada Denmark France Germany Greece Iceland Ireland Italy Luxembourg Netherlands Norway Portugal Spain Sweden Switzerland Turkey United Kingdom United States During the next 12 years, Japan, Finland, Australia, and New Zealand also joined the organisation. Yugoslavia had observer status in the organisation starting with the establishment of the OECD until its dissolution as a country. The OECD also created agencies such as the OECD Development Centre (1961), International Energy Agency (IEA, 1974), and Financial Action Task Force on Money Laundering. Unlike the organisations of the United Nations system, OECD uses the spelling "organisation" with an "s" in its name rather than "organization". Enlargement to