The private finance initiative (PFI) for the health service in the UK has come into question as a National Health Service (NHS) trust faces liquidation.
South London Healthcare NHS Trust, which is spending 14% of its income on repayments to a PFI, may be declared bankrupt with debts of £69m.
Apart from the financial issues, the trust has the longest waiting times for operations and longer-than-average waits in accident and emergency (A&E) departments.
South London Healthcare NHS Trust currently runs the Princess Royal University Hospital in Orpington, Queen Mary's Hospital in Sidcup and the Queen Elizabeth Hospital in Woolwich.
In the wake of the hospitals' financial crisis, the UK Health Secretary is planning to appoint a special administrator tasked with securing the trust's revenues.
Another 20 trusts are also reportedly finding themselves in the middle of a financial crisis and the government is blaming the PFI scheme signed under the Labour Government.
Andrew Haldenby, from the think tank Reform, told the BBC that other PFI schemes had delivered good hospitals and good value for taxpayers. But he warned that difficult decisions about the numbers of hospitals in England could not be postponed.
"One in five hospitals is in real financial difficulty. Every hospital - even if it is in the black right now - needs to be looking really hard at this. Although we are talking about South London today, every NHS chief exec needs to be looking at this today."