Opportunity Knocks is a British television and radio talent show originally hosted by Hughie Green, with a late-1980s revival hosted by Bob Monkhouse, and later by previous winner Les Dawson.
The original radio version started on the BBC Light Programme from 18 February to 29 September 1949 but moved to Radio Luxembourg in the 1950s. It was shown on ITV from 20 June 1956 to 29 August 1956, produced by Associated Rediffusion. A second run commenced on 11 July 1964 and lasted until 20 March 1978, produced first by ABC and then by Thames. Hughie Green presented a single episode of Opportunity Knocks for RTÉ in 1979. It was revived by the BBC from 21 March 1987 to 2 June 1990, hosted initially by Bob Monkhouse from 1987 to 1989 (under the title Bob Says Opportunity Knocks!) and subsequently by Les Dawson in 1990.