William Schumacher Massey (born 1920) is an American mathematician, known for his work in algebraic topology. The Massey product is named for him. He worked also on the formulation of spectral sequences by means of exact couples, and wrote several textbooks, including Algebraic Topology (ISBN 038797430X).
William Massey was born in Illinois in 1920. He was an undergraduate student at the University of Chicago. After serving in the U. S. Navy during World War II he received a PhD degree from Princeton University in 1949. His dissertation, entitled Classification of mappings of an (n+1)-dimensional space into an n-sphere, was written under the direction of Norman Steenrod. He spent two additional years at Princeton as a post-doctoral research assistant. He then taught for ten years on the faculty of Brown University. From 1960 till his retirement he was a professor at Yale University. He is now a Professor Emeritus at Yale.