Carl Fehmer (November 10, 1838 – 1923) was a prominent German-American Boston architect during the 19th century. Fehmer had already started his architectural career before his service in the Civil War, but became well-established afterward. With two key partnerships (with William Ralph Emerson from 1867 to 1873, and with Samuel Francis Page from 1882 to 1908), Fehmer designed a long list of residences in the Back Bay, department stores, major civic buildings, and landmarks such as the Boylston Building. All but a few of his designs are in Boston.