It's not immediately obvious why a committed cyclist and local Green Party activist who used to run a charity dealing with mental health in the criminal justice system should have been chosen 18 months ago as chief executive of the Churches Conservation Trust.
The trust looks after 332 Anglican churches, dating from Saxon times to the 19th century, that are no longer needed for worship. Much of its work consists of important but mundane jobs such as clearing blocked gutters, unblocking drains and replacing slipped slates.
But the trust is also involved in finding new uses for redundant churches, and that's where Truman comes in, with his grass-roots vision of finding a real community purpose for these buildings and breathing life into them once again.
The restoration of the Victorian gothic St Paul's church in Bristol and its lease to the circus school Circomedia for performance and community work is an example of the trust's new vision being put into practice (Third Sector, 12 January). The building now has a flying trapeze rig and a sprung dance floor, thanks to a £2.5m Heritage Lottery Fund Grant.
But Truman says that for him the trust isn't just about the buildings.
It's also about the people who could benefit from using them. He wants to raise the level of debate about redundant churches and help local communities decide the best use for them.
This means he doesn't want the trust to be in control all the time. "It is not going to be a top-down solution," he says. "There has to be a bottom-up solution, and that's one thing I am trying to turn around."
In rural areas, where communities have been particularly badly blighted by the closure of local shops, post offices and other meeting points, he says the trust wants churches to be used as community centres. It offers advice to communities on issues such as how to apply for grants or how a building could best be used.
But it's not just about rural churches. Following the success of the St Paul's project in Bristol, the trust is in the process of setting up similar schemes: a community centre at St Mary's in Sandwich, Kent, for example, and community music projects in churches in King's Lynn, Norfolk, and Sunderland on Teesside.
He wants the trust to be creative, innovative and open-minded about finding relevant new uses for redundant churches. He says it's not a problem attracting non-Christian community groups to buildings that have been Christian places of worship. "A lot of the people who approach us are from other faiths," he says.
The logistical problem of empty and disused churches is a huge challenge.
The trust's budget from the Church Commissioners and the Department of Culture, Media and Sport has been frozen for three years - a 7 per cent cut in real terms - even as the number of churches needing protection mushrooms.
In 2004, 30 more Anglican churches were made redundant, and the Ecclesiological Society estimates that this will grow to about 60 churches a year.
"The trust has traditionally looked after churches well, but the number of historic churches at risk is growing and the money is pretty static," says Truman. "We can't just keep adding more and more churches to the pile. We need to provide support and advice to get the churches back on their feet because it is the only way we will be able to cope with so many."
One consolation is that the appreciation of historic churches is not a minority interest, despite the decline of formal church-going. For the first time last year, the number of visitors to churches cared for by the trust exceeded a million.