Paul Hamilton Williams, Jr. (born September 19, 1940) is an American composer, singer-songwriter, and actor. He is perhaps best known for popular songs performed by a number of acts in the 1970s including Three Dog Night's rendition of "An Old Fashioned Love Song", Helen Reddy's "You and Me Against the World", David Bowie's "Fill Your Heart", and the Carpenters' "We've Only Just Begun" and "Rainy Days and Mondays", as well as his contributions to films, such as writing the lyrics to the #1 chart-topping "Evergreen", the love theme from A Star Is Born, starring Barbra Streisand, for which he won a Grammy for Song of the Year and an Academy Award for Best Original Song; and "Rainbow Connection" from The Muppet Movie. He also composed the enormously popular opening theme for The Love Boat, originally performed by Jack Jones, and later, by Dionne Warwick.

He has also had a variety of high-profile acting roles such as Little Enos Burdette in the 1977 action-comedy Smokey and the Bandit, and as the villainous Swan in Brian De Palma's Phantom of the Paradise (which Williams also co-scored, receiving an Oscar nomination in the process), as well as television, theater, and voice-over work for animation.