CEO, Block Jack Dorsey, best known as Twitter's co-founder, has led Block (formerly Square) since its founding in 2009. After stepping down as Twitter’s CEO in 2021, he has focused exclusively on Block’s operations. Under his leadership, Block has evolved from a simple mobile payments company into a diverse financial services firm encompassing peer-to-peer payments (Cash App), cryptocurrency initiatives (Spiral) and music streaming (Tidal). Jack has been particularly passionate about cryptocurrency adoption, implementing Bitcoin-focused projects within Block. His management style reportedly emphasises transparency and decentralisation, reflected in Block's corporate structure and product development approach. 6: Alfred F. Kelly Jr. Alfred F. Kelly Jr., Former CEO and Executive Chairman, Visa Former CEO and Executive Chairman, Visa Alfred F. Kelly Jr served as CEO of Visa from 2016 to 2024, and concluded his role as Executive Chairman in February 2024. Before joining Visa, he spent 23 years at American Express in various executive roles, including President from 2007 to 2010. During his tenure at Visa, Kelly oversaw the company's digital transformation and expansion into new payment technologies. He led Visa through significant acquisitions, including Currencycloud, and strengthened the company's position in emerging markets and cryptocurrency services. Between his roles at American Express and Visa, he served as CEO of Intersection, a technology and digital media company, and led the 2014 NY/NJ Super Bowl Host Company. In March 2024, he joined Berkshire Partners as an Advisory Director. Today, he serves as a Trustee of several institutions including New York Presbyterian Hospital and Boston College, and chairs the Board of the Mother Cabrini Health Foundation. 5: Eric Glyman