Seth-Smith, Monro & Matthew originated as Seth-Smith & Monro, an architectural practice established in London, England by William Howard Seth-Smith (1852-1928) and William Ernest Monro (1868-1945) in 1905. Following the death of Seth-Smith in 1928, Monro retained the original title of the firm until 1934 when a third partner, Alexander Edward Matthew (1903-1972), joined the practice. It was then renamed Seth-Smith, Monro & Matthew.
Seth-Smith, Monro & Matthew was active until at least the late 1950s. The address of Seth-Smith & Monro and Seth-Smith, Monro & Matthew was for much of its history 46 Lincoln's Inn Field, London. By 1950 they had relocated to 7 High Holborn, London. The firm was active until at least the late 1950s.
Work by Seth-Smith, Monro & Matthew included a dormitory for boys learning trades at 44–48, Latimer House, London (1938); and St. John Wood church, Eastbourne, Sussex (1956-57).