Robert Paul "Tad" Williams (born 14 March 1957 in San Jose, California) is an American writer. He is the international bestselling fantasy and science fiction author of the multivolume Memory, Sorrow, and Thorn series, Otherland series, and Shadowmarch series as well as the standalone novels Tailchaser's Song, The War of the Flowers, Caliban's Hour, and Child of an Ancient City. Most recently, Williams published The Bobby Dollar series.