Martin Greenfield (born Maxmilian Grünfeld; August 9, 1928 – March 20, 2024) was an American master tailor, based in Brooklyn, New York, specializing in men's suits. Described in 2014 as "the best men's tailor" in the United States, his list of clients included six U.S. presidents, as well as other notable politicians and celebrities. His company, Martin Greenfield Clothiers, also has a white-label business, fashioning men's suits for clothing lines DKNY and Rag & Bone and the television show Boardwalk Empire. Greenfield was a Holocaust survivor, having been imprisoned as a teenager at Auschwitz where the rest of his immediate family were murdered.