Sabatino is the second general counsel to leave United in under a year. Paul Lovejoy resigned in November 2009 ''for personal reasons,'' a company spokesperson said at the time.
In his role at United Continental Holdings, Mr. Hart will be responsible for managing the company's legal affairs worldwide, and will report directly to President and CEO Jeff Smisek.
Mr. Hart most recently served as executive vice president, general counsel and corporate secretary at Sara Lee Corporation, where he directed global legal operations for the corporation.
Before Sara Lee, Mr. Hart was a partner with Sonnenschein, Nath & Rosenthal in Chicago. He also previously served as special assistant to the general counsel at the U.S. Department of the Treasury in Washington, D.C.
Hart earned his Juris Doctorate degree from the University of Chicago Law School, and a bachelor's degree in philosophy and English from the University of Michigan.
United Continental Holdings, Inc. is the holding company for both United Airlines and Continental Airlines. Together with United Express, Continental Express and Continental Connection, these airlines operate a total of approximately 5,800 flights a day to 371 airports on six continents. United's and Continental's more than 80,000 employees reside in every U.S. state and in many countries around the world.