William J. Hornbuckle IV is an American businessman and native of Arizona who succeeded Thomas J. Murren as president and CEO of MGM Resorts International on August 1, 2020, amid the COVID-19 crisis impacting the hospitality and gaming sectors. Prior to this role, Hornbuckle spent over a decade at MGM, rising through positions such as president of global gaming and operations (2012-2019) and chief operating officer (2019-2020). His earlier career included executive roles at Sun International Hotels as CFO and later CEO of its U.S. operations, and at Park Place Entertainment (predecessor to Caesars Entertainment), where he contributed to international expansions in gaming and resorts. Hornbuckle began his professional journey as an auditor at Arthur Andersen & Co. after graduating from Arizona State University. Under his leadership, MGM has pursued digital growth through the BetMGM joint venture with Entain (launched 2018, rebranded 2021), navigated a 2023 cyberattack by the ALPHV/BlackCat group that caused temporary casino shutdowns, and managed workforce reductions during the pandemic, which drew criticism from labor groups. He continues to guide MGM's strategy in integrated resorts, sports betting, and entertainment amid evolving U.S. gaming regulations.