Cornish's media career began in radio at 4IP in Ipswich, before he was subsequently hired by Brisbane radio station4BH as a piano player. When television arrived in Queensland, Cornish was the first person to appear when Brisbane's Channel 9 launched in 1959, beginning a long association with the station where as well as being an on air presenter, he also served as the station's program manager, assistant general manager, and general manager. In the early 1960's, Cornish hosted Channel 9's local variety showBrisbane Tonight and from 1978 until 1983, he also hosted the station's local talent showStairway to the Stars. Cornish produced a Royal Command Performance at Her Majesty's Theatre in Brisbane in 1982 as part of the Commonwealth Games, which Cornish has often described as the highlight of his career. After leaving Channel 9 in 1985, Cornish moved to Channel 7 where he worked as a corporate development manager for several years before taking up the position as the director of children's television for the Australian Television Network. In 1989, Cornish briefly returned to Queensland television screens as the weekend newsreader for Channel 10 in Brisbane. Cornish was then employed as a manager of corporate development at the Queensland Arts Council from 1993 until 2000, and a development manager for the Queensland Orchestra from 2000 until 2001. Despite his long association with the station, Cornish criticised Channel Nine Brisbane in 2011 following the infamous Choppergate controversy when the station was caught out staging fake live crosses. Cornish said he believed the station's reputation had been "sullied and damaged" by the scandal and that it would take time for Channel 9 to regain its credibility. However, within three years, Nine News Queensland would regain the lead in the local ratings. When analogue television signals were switched off in Brisbane on 28 May 2013, Cornish was invited back to Channel 9 to be granted the honour of switching off the station's analogue transmission signal. He said the experience had left him "a bit teary". Cornish is credited with helping raise millions of dollars for charity including raising $9 million from various telethons and benefit concerts he produced. Now in retirement, Cornish is a resident of the Renaissance Retirement Village at Victoria Point where he is credited with establishing an entertainment program. He and the other residents at the facility published a nude calendar in 2013 featuring semi-nude photos of themselves to raise money for charity, Look Good Feel Better.
