Following his retirement from the NBA, Thomas took a front office position as part owner and Executive Vice President of the Toronto Raptors expansion team.  He served as head coach of the Indiana Pacers, President, General Manager and Head Coach of the New York Knicks and was owner of the Continental Basketball Association. He also served as the head men's basketball coach at Florida International University.

An innovator and entrepreneur, Thomas founded Enlighten Sports Inc., a full-service web development group specializing in sports marketing in 1999. When at the Continental Basketball Association, Thomas launched partnerships with Enlighten Sports and the University of Colorado and the CBA. The new websites allowed fans to watch live game webcasts, use live shot charts, chat with players and more. Thomas said the internet was “an integral part of [the CBA’s] strategy to provide engaging and entertaining content for fans.” Also, while Thomas was with the Continental Basketball Association he launched a partnership with SEASONTICKET.com to bring personalized video highlights and scores to fans across the country as well as be a portal for All-Star League voting. With Thomas’ foresight, he realized that streaming video would be the future of news and entertainment.

Thomas began his business career mid-way through his NBA tenure. In his free time, he read up on business and related issues, met with contacts and eventually invested in a series of ventures, including a large chain of printing franchises, American Speedy Printing. As his business mentor and partner Rick Inatome explained, “He’s the definitive study of ‘picture it and it becomes’” — a motto Thomas continues to bring to all of his business ventures.

As Chairman and CEO of Isiah International, Thomas successfully applies that spirit to the business world, having built companies that specialize in waste removal & recycling, multi-family housing, and the sports industries. Thomas is also the sole owner of four companies: Isiah International Holdings, an investment holdings company, GRE3N, Isiah International Real Estate, a multi-housing development firm, and Isiah Capital, a private equity investment firm. Thomas also co-owns the waste removal’s sister company, RE3 Recycling, with his daughter, Lauren. Most recently, Thomas is also involved in a $300 million development deal for a mixed-use complex on 9.5 acres of land at the Illinois Medical District Commission. Isiah is also on the Cannabis Trade Federation Diversity, Equity, and Inclusion Task Force. The DEI Task Force is comprised of a diverse and experienced collection of prominent national minority business and cannabis industry leaders.