The son of the actor Rex Harrison, he was best known for recording the hit song The Windmills Of Your Mind on The Thomas Crown Affair soundtrack.
It won best song at the 1968 Oscars and was later covered by artists including Dusty Springfield.
Harrison spent much of his life in America, as an actor and performer, but moved back to the UK in the last decade or so to live in South Devon.
He once said, of recording The Windmills Of Your Mind: "It didn't seem like a big deal at the time. I went to the studio one afternoon and sang it and pretty much forgot about it."
"Windmills Of Your Mind":
In news closer to home, good that Medford teachers are flexing their muscles. The contract deal the Medford School District is offering is pathetic. The teachers there are pitifully underpaid and overworked.