From 1974 to 2002, he was employed by Jefferies and Company, a global investment bank specializing in small and mid-cap companies. In 1984, he moved to London to start and act as Managing Director of Jefferies International, which now has offices in Europe, Asia, and Australia. In 1987, he became CEO of Jefferies. That same year he started the Investment Technology Group, which is now a major electronic institutional brokerage, listed on the New York Stock Exchange during the 90s. He is now Chairman Emeritus of the firm.

He is a former director of the NASD and served as Chairman of the committee, which resulted in the spin-off of NASDAQ. He subsequently served on the Board of NASDAQ as a member of the Executive Committee and Chairman of the CEO search committee. He is also a former director of the Securities Industry Association.

Mr. Baxter's civic activities include: Chairman of the Board of Alliance for College-Ready Public Schools, an organization dedicated to starting a number of charter schools in Los Angeles; Chairman of the Board of After-School All Stars, an after-school program for middle-school children; Board Member, California Institute of the Arts; Member, Governor Schwarzenegger's Commission for Jobs and Economic Growth; Vice Chairman of the Board of the Los Angeles Opera, whose budget more than doubled during his tenure as President; Chairman of the Executive Committee, Los Angeles County Museum of Art, which is undergoing a major building campaign; Trustee, University of California Berkeley Foundation; and Trustee, I Have A Dream Foundation, LA Chapter.

He is the recipient of the Bet Tzedek, House of Justice and the Getty House (Mayor's Residence) City of Angels awards.