Sir Sacheverell Reresby Sitwell, 6th Baronet, CH (/sæˈʃɛvərəl/; 15 November 1897 – 1 October 1988) was an English writer, particularly on baroque architecture, and an art and music critic.

He was the youngest child of Sir George Sitwell, 4th Baronet, of Renishaw Hall, and the former Lady Ida Emily Augusta Denison.

His maternal grandparents were William Denison, 1st Earl of Londesborough and Lady Edith Somerset (a daughter of the 7th Duke of Beaufort), who claimed descent through female lines from the Plantagenets.

After the war he went to Balliol College, Oxford but did not complete a degree, and was heavily involved in Osbert and Edith's projects.

[4] A series of books on music and musicians - including Mozart (1932), Liszt (1934) and shorter essays on Scarlatti, Offenbach and Tchaikovsky (Valse des Fleurs, 1941) - were also highly influential.

The Dance of the Quick and the Dead (1936) established a new strand of his work, evoking "outcast and vagabond societies; their music, their dress, their customs and rituals".

The personal correspondence of Doble, preserved at the Harry Ransom Center at the University of Texas, include letters with David Stuart Horner and Frank Magro, Osbert Sitwell's partners, and friends like Lawrence Audrain, John Lehmann, Loelia Lindsay, René Massigli, Evelyn Waugh, and Mae West.