At some point before 1930, the UMW became a member of the American Federation of Labor. The UMW leadership was part of the driving force to change the way workers were organized, and the UMW was one of the charter members when the new Congress of Industrial Organizations was formed in 1935. However, the AFL leadership did not agree with the philosophy of industrial unionization, and the UMW and nine other unions that had formed the CIO were kicked out of the AFL in 1937.