Today there is a boom in private hospital building; 'pay as you need' GP schemes are being set up; subscriptions to health insurance schemes for private medical care have grown by more than a third in the past couple of years - one person in 15 now has private health cover.

There are furious arguments over whether those who pay are 'jumping the queue' - or whether in fact they are making things easier for the NHS to cope with those who can't - or won't - pay.

Is private medicine a complete alternative to the NHS, or is there anything health insurance won't pay for? Where do the doctors and nurses in the private hospitals come from? And as private medicine grows, what will happen to the NHS?
"Horizon" looks at how the two systems, private and public, are linked and investigates the implications for the health needs of the nation.