Accusations that private equity achieves results through risky financial trickery, combined with the vast rewards reaped by private equity directors have resulted in a less than favourable image for the sector. But Shaks Ghosh, the former head of homelessness charity Crisis and now chief executive at the Private Equity Foundation (PEF), has seen the positive face of the industry. "You would not believe the amount of time they [private equity firms] put into the PEF," she says. "Every day I meet dynamic, stimulating people who are genuine, committed and who really want to make a difference. And they want to see their money being used effectively."

The foundation's mission is to empower young people to reach their full potential (to be "learners, workers and good citizens") by investing money and expertise from the private equity community to help charities grow and have more impact. If Ghosh thought for a minute that the sector was involved merely for enhancing its reputation, she wouldn't be there. "If this was just about PR, they'd write me a cheque and go away," she says. "These people are successful because they've looked after their money; they're used to making a difference, having an impact, and by being involved in the foundation they could be doing something world-changing."

Ghosh is accustomed to defending her cause. When she led the repositioning of Crisis from focusing on feeding and housing the homeless to delivering education and skills, she came in for flak. But all change is difficult, she reasons. "What we did was focus the organisation on helping people to rebuild their lives. We closed down a lot of the old services, and that wasn't easy. It took a long time to persuade people that this was the right way forward. But the reality is probably that Crisis would have been an irrelevance if we had stayed the same as we were."

Ghosh loves the foundation's collaborative business model: "Private equity firms are giving collectively through the PEF with considerably more impact. And we run our portfolio [currently 13 charities] pretty much like a private equity firm. We're saying to the charities, 'by working together we can shift the needle on the important social issue of disadvantaged young people'."

The foundation intends to have only up to 16 charities in its portfolio at any one time. Once it has helped those to scale, they will exit and be replaced. "We rarely give anything less than £500,000," says Ghosh. "We don't believe in dribbling money into the sand. It's large amounts of money to make a really big difference. We've got a mix of charity and business that I hope will affect powerful social change."