The NHS was founded on a belief that the provision of health and health services is a moral and social duty of a civilised society rather than a commodity to be bought and sold.

The service has evolved since 1948 but it remains essentially free at the point of delivery. Has that ideal been outgrown? The answer is an emphatic no.

This does not mean we can be complacent. A recent comparison of six countries by the Commonwealth Fund ranked us first for equity and patient safety, but we still do less well on effectiveness, access and patient-centeredness. Overall we were ranked third - not evidence of a system past its prime, but a compelling argument for improvement and a demonstration of achievement.

The challenge is to ensure that our equitable system is also responsive and sensitive to the needs of much more consumerist patients.

We do not have unlimited funds but neither does any other healthcare system. All governments are united in the drive to reduce costs and cannot avoid becoming embroiled, even where the funding regime is insurance.

We have to think about productivity; every pound spent carelessly is an attack on the values of the NHS. We also need to balance the priorities we give to different conditions as our ability to intervene increases. Setting priorities and deciding what not to do is a necessary part of every healthcare system, but in the UK we do not decide based on ability to pay or market forces.

More open debate with the public is needed. The local decision-making structures of primary care trusts will drive these debates; one person's localism is another's postcode lottery. We also know patients have a higher opinion of the NHS than the public does, and we must show the wider population they are getting a good service and value for money.

It is not wrong to bring in the private sector and alternative providers for healthcare. This does not distort the central value of a free NHS. Commitment to funding through tax helps ensure equity for patients and makes economic sense.

I believe that an NHS based on social solidarity is the jewel in the crown of a civilised society. We can debate at the party conferences about becoming more responsive to patients' needs and being more productive, but the fundamental principle is one of which we should all be proud.

Dr Gill Morgan is chief executive of the NHS Confederation