The Government should defend the elements of the Health and Social Care bill that encourage competition, a new report urges.
The call from centre right think tank Reform profiles new international evidence on the benefits of competition for patients.
Reform has published ten case studies from around the world suggesting that competition allows new organisations to run services better, more efficiently and often at lower cost.
The publication came as Deputy Prime Minister Nick Clegg and Baroness Williams this week sent a letter to Lib Dems in the Commons and the Lords setting out final changes they want to see to the bill to limit the role of competition in the NHS.
They promised to back measures 'to protect the NHS from any threat of takeover from US-style healthcare providers by insulating the NHS from the full force of competition law'.
Health secretary Andrew Lansley accepted a clutch of Lib Dem amendments requiring CCGs to publish a register of interests of members and employees earlier this week.
Reform´s case studies included one from the US where privately-run microclinics claimed to provide care 50% cheaper than visiting a GP and another where a private company coordinated services for mental illness cutting the cost of hospitalisations for children by 20%.
Nick Seddon, Reform's deputy director, said: 'Parliament should pass the health bill including the clauses on competition, not because the bill is perfect but because the NHS must move on.
If the NHS wants to be the best in the world, it should learn from the best in the world and the radical changes that other countries are implementing.'
Dr David Jenner, a member of the NHS alliance and a GP in Cullompton, Devon said: 'My own personal feeling is that the bill has been so much amended it ought to be dropped. Further amendments around the words of competition won´t restore the confidence of the public or of health professionals.
'In terms of whether the Lib Dem´s amendments will make any difference to competition in practice, I simply don´t know. It would take lawyers weeks to unravel the meaning of the bill in this respect and frankly I´m not sure anyone knows what it still means.'
