Adrian Marten George Darby, OBE (born 25 September 1937) is a British conservationist and academic.
He subsequently served as chairman of Europe's largest nature conservation organization the RSPB (1986–1993), and became vice-president from 1996 onwards.
He served as chairman of the Joint Nature Conservation Committee of the United Kingdom from 2004 to 2007.
Darby has served as a regional committee member of the National Trust; a fellow (governor) of Eton College (1979–1994); a county committee member of the Country Landowners Association.
He is married to acupuncturist Lady Meriel Darby, daughter of the former Prime Minister Alec Douglas-Home.