T revor Rees-Jones is a self-made American billionaire who built his fortune in the oil and gas industry. A former bankruptcy lawyer, he founded his own oil and gas exploration company, Rees-Jones Oil & Minerals, in the 1980s. He later founded his primary company, Chief Oil & Gas. He achieved massive success and became a billionaire by being one of the pioneers in unlocking the natural gas reserves of the Barnett Shale in North-central Texas, one of the largest onshore natural gas fields in the United States.

He and his company were at the forefront of combining horizontal drilling and hydraulic fracturing (fracking) techniques to extract gas from the shale rock, a technological revolution that transformed the American energy landscape. He has since sold the bulk of his Barnett Shale assets for billions of dollars. He is also a major philanthropist in his hometown of Dallas, having given away hundreds of millions of dollars to various causes, including education, healthcare, and conservation. He and his wife have signed the Giving Pledge.