William H. "Bill" Wynn was the first president of the United Food and Commercial Workers International Union (UFCW), and the last president of the Retail Clerks International Union (RCIU), after the latter merged with the Amalgamated Meat Cutters and Butcher Workmen of North America in 1979, to create the UFCW. He is best known for playing a leading role in completing the above merger, and, through that effort, making a pivotal contribution to the creation of the largest union affiliated to the AFL–CIO at the time. Wynn is also credited for instituting a fierce organizing culture at UFCW.