Through the 1930s, the "Laws" were promulgated by the Portland Club of London and the Whist Club of New York. From the 1940s onwards, their roles were supplemented by British Bridge League and European Bridge League on the European side, and American Contract Bridge League Laws Commission from the American side. From 1975 onwards, "Laws" were also promulgated by the World Bridge Federation Laws Commission, which claims the sole responsibility both for their content and their interpretation. In the latest edition, published in June 2017, the WBF acknowledged the historic cooperation of the Portland Club, the European Bridge League, and the American Contract Bridge League.