The problem is compounded by the diversity of business offerings that describe themselves as social enterprises - but that diversity is also a strength. The profit motive can be harnessed for social good in many ways, as these three businesses prove.
TRADING BEEF KITCHEN
Some business concepts are so obvious that it's hard to imagine why no one thought of them before. The Beef Kitchen is such a concept - a mobile catering van selling organic beef sandwiches outside Chelsea Football Club.
The social enterprise, which turns over £20,000 a year, has been feeding football fans on match days since 2005. It provides training and work for residents of the Sir Oswald Stoll Foundation, an independent living charity for ex-service personnel. The foundation - based, like Chelsea FC, in Fulham Road, west London - exists partly to tackle homelessness among those leaving the armed forces: 40 per cent of its tenants have been homeless and many have had addiction problems.
Beef Kitchen was the brainchild of Bob Barrett, one of the foundation's tenants. The foundation provided the van, but tenants do the work, usually in teams of four. One unexpected benefit has been the new-found confidence that self-employment has brought. "Social enterprise made sense as a business model for our tenants because they can lack confidence and motivation," says Katie Truss, the foundation's fundraising manager.
The foundation is now expanding its traditional activities. Last month it launched a second social enterprise venture, Pryors Bank Cafe, based in Bishops Park near Fulham Football Club, also in west London, with £85,000 start-up capital from donors, government grants and the Royal British Legion. The cafe will provide tenants with an apprenticeship programme.
When a social enterprise concept matches the political zeitgeist, project funding can be forthcoming.
Bikeworks founder and director David Miller and his business partner Jim Blakemore had a hunch that cycling was a potential growth market when they set up the community interest company in 2006. But Miller says the company struck gold that year when the Government made £1m available to local authorities to train schoolchildren to the National Cycle Training Standard - the new name for the old Cycling Proficiency Test. "Just as we started to get going, we very quickly picked up a £100,000 contract from Newham Council," he says.
The organisation, based in Hackney, east London, not only trains cyclists but also counts consultancy, employment training, retail and a bike-recycling scheme among its enterprising projects. It expects to turn over £500,000 this financial year and says 60 per cent of its income comes from local authorities.
Funding comes from diverse sources and Bikeworks is in talks with a primary care trust to provide cycling training as part of patient recovery programmes. The organisation's success, says Miller, lies in its flexibility. "We think differently because, although we have ethical values, we are equally focused on running a viable business," he says. "We'll do anything provided it fits with our ethos, because we have to be entrepreneurial - it's what we're good at."
COMMUNITY SUNLIGHT DEVELOPMENT TRUST
The trust typifies the type of community-led, entrepreneurial model that the Government and opposition want public services to emulate. Politicians are keen to get to know the trust's community resource centre and enterprise hub in Gillingham, Kent.
Prime Minister Gordon Brown met the management team last year, and this year the Conservatives launched their green paper for the voluntary sector there.
The trust's resource centre includes a family centre funded by the local authority, a GP practice funded by the local primary care trust, a cafe and facilities for 90 community groups, such as meeting rooms, an events hall and a radio station. The trust expects to turn over £1.5m this fiscal year from commercial activities that include a consultancy, a design studio, training franchises and a recording studio.
"Sunlight began as a National Lottery-funded healthy living centre in 1999," says chief executive Peter Holbrook. "The money ran out in 2006, so we had to pack up or think of ways to sustain revenue."
Its successes include Parentis, the trust's parent support training course, which has become a franchise for sale to local councils. Holbrook says the course is an example of how social enterprises can generate profit from projects that are proven to work.