Stanley John Sadie, CBE (/ˈseɪdi/; 30 October 1930, Wembley – 21 March 2005, Cossington, Somerset) was an influential and prolific British musicologist, music critic, and editor. He was editor of the sixth edition of the Grove Dictionary of Music and Musicians (1980), which was published as the first edition of the New Grove Dictionary of Music and Musicians.
Sadie was educated at St Paul's School, London, and Gonville and Caius College, Cambridge, where he read music under Thurston Dart. Sadie earned a Bachelor of Arts and Bachelor of Music degrees in 1953, a Master of Arts degree in 1957, and a PhD in 1958. His doctoral dissertation was on mid-eighteenth-century British chamber music. After Cambridge, he taught at Trinity College of Music, London (1957–1965).
Sadie then turned to music journalism, becoming music critic for The Times (1964–1981), and contributing reviews to the Financial Times after 1981, when he had to leave his position and The Times because of his commitments to the Grove and other scholarly work. He was editor of The Musical Times 1967–1987.
From 1970 Sadie was editor of what was planned to be the sixth edition of the Grove Dictionary of Music and Musicians (1980). Sadie oversaw major changes to the Dictionary, which grew from nine volumes to 20, and was published as the New Grove Dictionary of Music and Musicians (New Grove), and is now referred to as the first edition under that name. He was also an important force behind the second edition of New Grove (2001), which grew further to 29 volumes. Sadie also oversaw a major expansion of the Grove franchise, editing the one-volume Grove Concise Dictionary of Music (1988), and several spinoff dictionaries, such as the New Grove Dictionary of Musical Instruments (three volumes, 1984), the New Grove Dictionary of American Music, (with H. Wiley Hitchcock, four volumes, 1986), and the New Grove Dictionary of Opera (four volumes, 1992). He also edited composer biographies based on the entries in Grove.
Outside his work on the Grove Dictionaries, Sadie edited the Man and Music volumes accompanying a television series (1989–1993). He was a renowned Mozart scholar, publishing several books. He also was instrumental in saving the Mayfair house where George Frideric Handel once lived, turning it into the Handel House Museum.
He was president of the Royal Musical Association (1989–94), of the International Musicological Society (1992–97), and of the Trustees of the Holst Birthplace Museum in Cheltenham.
He was also an accomplished bassoonist.
Sadie died at his home in Cossington, Somerset, 21 March 2005, of amyotrophic lateral sclerosis (Lou Gehrig's disease), which had been diagnosed only a few weeks earlier.
In 1982, Sadie was appointed CBE (Commander of the Order of the British Empire). He received an honorary Doctor of Letters from the University of Leicester in 1982, and was elected honorary fellow of the Royal College of Music in 1994 and Gonville and Caius College, Cambridge. In 2005, Sadie became a Handel Music Prize laureate.
- American Musicological Society, corresponding member, 1996
- Royal Musical Association, president 1989–1984
- The Critics' Circle
- International Musicological Society, president 1992–1997
- Stanley Sadie Archive Project, Cambridge University Library