In 1935, he left government service to become the special counsel to the president (Kenneth R. Kingsbury) of Standard Oil of California (now Chevron Corporation) in San Francisco, and began his long career as an oilman. Another two years later he became a partner at the firm Pillsbury Madison Sutro (now known as Pillsbury Winthrop Shaw Pittman), which was the company's outside counsel. It was at Standard Oil of California that he began a lifelong business association and friendship with his mentor Ralph K. Davies. In 1941, he was called back to Washington, D.C. during World War II as Solicitor of the Petroleum Administration for War, helping develop U.S. energy policy during the war, including the Cole Pipeline Act of 1941, and later as a member of the Committee on Reparations, the National Petroleum Council and the American Petroleum Institute. In 1944, after developing a relationship with Paul G. Blazer, he became Vice Chairman and President of Ashland Oil and Refining Co. (now Ashland Inc.). Later positions included Executive Vice President at Signal Oil & Gas under Samuel B. Mosher (1952), President of Union Texas Petroleum (1960) and Executive Vice President of Allied Signal (all now Honeywell) (1967), Union Texas Petroleum Holdings was later sold by Allied Signal to ARCO and merged into BP, until his semi-retirement in 1969.