Sharp was born in Bellevue Hill, New South Wales in 1942, and educated at Cranbrook private school, where one of his teachers was the artist Justin O'Brien.

For most of the 1970s and beyond, Sharp's work and life was dominated by two major interests: Sydney's Luna Park and the entertainer Tiny Tim.

In 1979, as pressure mounted to redevelop the prime harbourside site, a fire in the Luna Park Ghost Train claimed seven lives, including a father and his two sons and four 13-year-old schoolmates.

The fire was a turning point in Sharp's life; like many others he firmly believed that it was a deliberate act of terrorism aimed at destroying the park and making the site available for redevelopment.

[citation needed] In the mid-1990s, Sharp helped broker a reconciliation between the Sydney Opera House and Jørn Utzon, who subsequently developed a set of design principles to guide the building's future.