Frizell joins as executive director, media, and will lead the agency's 'connector' team - a group of 16 dedicated media specialists.
His career marks him out as one of the country's most accomplished broadcast journalists, having worked as a correspondent with Reuters, Sky News and ITV, as well as taking the reins of GMTV, then the most-watched UK television breakfast show.
Until 2010, Frizell was responsible for 900 hours per year of live topical programming, broadcasting daily to five million viewers.
He was instrumental in persuading former prime minister Tony Blair to regularly appear on the GMTV sofa and has also won the Royal Television Society Award for News Reporting.
Most recently, Frizell was the UK correspondent for Australian TV station Channel 7. He is married to former GMTV broadcaster Fiona Phillips.
Talking to PRWeek, Frizell said of his move: ‘Public relations and journalism are no longer as different as some of my media contemporaries like to make out. The idea that PR is only about selling stuff is completely outdating – the dark side is becoming a lot lighter.’
Pointing to a number of ex-GMTV colleagues who have moved into senior posts in the industry, including Edelman’s Ed Williams, Asda's Sian Jarvis and Burson-Marsteller’s Katie Mayler, he argues that public relations has become a natural home for the storytelling skills of broadcast journalists.
He added: ‘I see the team of connectors at GolinHarris as journalists because they all have that gut instinct for a good story and have a deep understanding of the media landscape.’
Frizell will sit on the board of the Interpublic-owned agency and report to newly promoted London deputy MD and head of consumer Bibi Hilton.
Hilton said: 'Martin's mix of experience as a media strategist and national news editor makes him the perfect candidate to lead and develop our connector community. He knows instinctively what makes a media story and how to balance that against the client's objectives to achieve really strong results.'
She added that the appointment also reflected the increasing ‘irrelevance’ of press releases, meaning that broadcast experience such as Frizell’s was becoming increasingly important in developing fresh content ideas for clients.
GolinHarris undertook a major organisational revamp last year, building its structure around four global communities of dedicated specialists - strategists, creators, connectors and catalysts.
This 'G4' model was instigated in response to the influence of digital and social media in comms.