She has practiced law in the areas of entertainment, broadcasting, and charitable foundations. She served as Vice President and General Counsel of Harpo Productions, Inc. and then The Oprah Winfrey Foundations. As General Counsel for Harpo, Ms. Tanchum had overall responsibility for all legal aspects of the company including pre-publication review of The Oprah Winfrey Show, contract negotiations, FCC matters, and legal decisions in the areas of labor, trademark, and music. In 1998, she managed a high profile first amendment trial brought against The Oprah Winfrey Show by Texas Beef Feeders.