William James Joseph Lombardy (December 4, 1937 – October 13, 2017) was an American chess grandmaster, chess writer, teacher, and Catholic priest. He is best known for being Bobby Fischer's coach and second during the World Chess Championship 1972. Lombardy also had a successful chess career of his own, securing multiple titles such as the World Junior Championship in 1957 and three U.S. Open Championships.
Lombardy was born in New York City and started playing chess in early adolescence. He was a leading player in the U.S. while still a teenager, and won several national titles. He became an International Grandmaster in 1960. His most famous student, Bobby Fischer, was first introduced to professional chess by Lombardy as a child. He continued to guide Fischer throughout his career, particularly during Fischer's world title match in 1972 against Boris Spassky.
Lombardy was educated as a priest and after several years of service, was relieved of his priestly obligations in 1978 to care for a child from a troubled family. He continued to be active in chess as a teacher, but increasingly struggled with health and financial issues. He spent his later years in New York City and died there in 2017. Many of his contributions to chess — both through his own play and his coaching of Fischer — remain highly respected by the chess community.