Damon Buffini, boss of Permira, has rejected union claims that private equity companies destroy jobs.
He says that he has invited leaders of the GMB union who have criticised him to a meeting to discuss the issues.
"In a global economy there is no job security unless the business is profitable and sustainable and that it what we're doing," he told the BBC.
Private equity companies use clients' money and borrowed money to buy whole companies and try to turn them around.
Unions have been critical of the treatment of employees at two of Permira's businesses: the AA and Birds Eye.
The AA got rid of 3,000 staff - more than a quarter of its workforce - while under Permira's ownership.
Birds Eye cut 490 of its 1,250 UK staff when it closed its Hull factory.
But Mr Buffini takes the examples of New Look and Travelodge as businesses that have expanded and taken on extra staff since Permira invested in them.
"New Look... under our ownership put on nearly a million more square foot of retail space, Travelodge... built a hundred new hotels during our ownership. "
"Consequently they both have become strong very very good businesses - as part of that they also employ thousands more people."
In his first broadcast interview, Mr Buffini accepted that private equity has to be more transparent.
"We do believe that we have to be more open, that we have to communicate more about what we do, that we have to encourage our companies to disclose more about what they're doing but that's OK because I think we have a very good story to tell."