By Ross Hawkins
BBC News political correspondent
The Tories say their plans will be cheaper than a national database
The Conservatives want to let you view your health records online.
All they have to do first is dismantle one of the biggest civil IT projects in the world.
Shadow health secretary Andrew Lansley made headlines when he told the BBC about plans to give patients access to their medical histories through their home PCs.
But to achieve that the Tories want to pick apart the massive NHS computer project known as the National Programme for IT.
Its goal is to electronically link all GPs and hospitals in England.
Its price tag is £12.7bn, and part of the project is at least four years late. It has long been the target of criticism from MPs, medics and the media.
The National Programme also goes against the current Conservative ethos.
They want to see local decision-making. So they plan to halt and renegotiate the current contracts, and let individual primary care trusts and GP practices negotiate their own, much smaller agreements and run their own databases.
Providing the companies they hire make sure their systems work together, the Tories think this model of lots of small deals will prove cheaper and more efficient than Labour's plans.
But they have not been allowed to see the current contracts. So they do not know what penalties they would have to pay to cancel or change the standing agreements.
That means they cannot say how much their policy would cost, or how long it would take to implement.
And to complicate matters the Conservatives might want to keep parts of the system.
Some elements - like the electronic delivery of X-rays - are up and working.
The Department of Health says more than 15 million hospital appointments have been made using the computerised Choose and Book system.
All of which means the shadow minister who would have to make good the Conservative health promises - Stephen O'Brien - has a tricky job.
As a former director of a FTSE 100 company he is confident of his ability to get a good deal from those IT firms that signed contracts to deliver the current NHS plans.
If the Conservatives win the next election the fate of his scheme to reshape the NHS's computers may well rest not on debates on the floor of the House of Commons, but on negotiations with IT firms in the privacy of a Department of Health office.
His efforts there will test how well the Conservative vision of local decision-making can survive the reality of government.