Marianne Deborah Williamson is an American author, speaker, and politician. She began her professional career as spiritual leader of the Church of Today, a Unity Church in Warren, Michigan. Williamson has written several self-help books, including A Return to Love: Reflections on the Principles of A Course in Miracles in 1992, which became a New York Times Best Seller. She was launched into prominence by Oprah Winfrey, being a frequent guest on her daytime talk show and becoming known as her "spiritual advisor".