Duke also serves on the board of Directors for the Retail Industry Leaders Association and Arvest Bank's community advisory board. He formerly held positions with a number of Retailers, including Federated Department Stores, May Department Stores, and Venture Stores. Duke earned a BS in Industrial Engineering from the Georgia Institute of Technology in 1971, where he joined the Delta Sigma Phi Fraternity, and now serves as a member of the institution's advisory board. He sits on the Board of Directors of the Consumer Goods Forum.

Duke joined Wal-Mart in 1995, serving as the executive in charge of the company's international operations. He became the CEO of Wal-Mart in February 2009.

In 2010 he set goals to make Wal-Mart Energy efficient as possible and to open Wal-Marts in countries like Russia. In 2012, his salary was $18.2 million. In 2013, press reports indicated that the total value of Duke's pension, deferred compensation and other retirement accounts totaled over $113 million.

Duke said in 2012 that his biggest regret as CEO was not investing more in e-commerce to better compete with Amazon. "I wish we had moved faster. We've proven ourselves to be successful in many areas, and I simply wonder why we didn't move more quickly. This is especially true for e-commerce," Duke said at the time. "Right now we're making tremendous progress, and the Business is moving, but we should have moved faster to expand this area."

Duke ranked No. 10 on Forbes list of The World’s Most Powerful People in 2013. That same year, Wal-Mart ranked No. 15 on Forbes list of Most Patriotic Brands—and the only retailer on the list—as voted by U.S. consumers. As of November 25th, 2013, Duke's tenure as CEO ended with his sudden replacement decided by Walmart's Board.