TV historian Dan Snow has joined the Clink charity as group communications ambassador.
The presenter has fronted a number of documentaries and made regular appearances on the BBC's The One Show.
He said his involvement with the charity, which operates restaurants in prisons, was down to his interest in crime and punishment, and the renewed focus on rehabilitation.
"To bear witness to how far we have come with training initiatives such as the Clink Charity and restaurants shows how much we have progressed as a society," Snow said.
"Focusing on rehabilitation rather than punishment has real potential to reduce the constant spiral of crime for the benefit of society as a whole and the Clink demonstrates this every day."
The Clink charity chief executive Chris Moore added that Snow had been a supporter of the initiative since the first restaurant opened in 2009. "Someone of Dan's vast knowledge and media experience is hugely beneficial in raising the charity's profile," he said. "Having a respected, friendly and recognisable face on-board enables us to reach new audiences."
Snow's wife, Edwina Grosvenor, has had a long term interest in prison reform and is a trustee of the Clink charity.
The charity operates four restaurants in prisons, training prisoners in chef, front of house and horticulture skills that can lead to professional qualifications and employment upon release.