A White Paper due in early July will outline the DoH's first detailed vision of an NHS in England commissioned by GPs.
Crucial questions remain over how health secretary Andrew Lansley will impose his policy on the profession, and who will be accountable when it goes wrong.
NHS Alliance contract lead Dr David Jenner says the government is considering taking GPs' provider contracts away if they fail when commissioning.
'It is the crucial question,' says Dr Jenner. 'What if it goes wrong? In some places, it will go wrong. What is the incentive to get involved if the risk is losing my provider contract?'
'There is still no detail about who is accountable,' says GPC member Dr Nigel Watson. 'You could be looking at GP groups with budgets of up to £200 million, covering 500,000 people.'
GPs also want to know what the Tories' pre-election pledge to make commissioning 'compulsory' will mean in practice. How will Mr Lansley make GPs commission where practice-based commissioning failed?
Dr Paul Charlson, chairman of the Conservative Medical Society, says there will be less money available in the GP contract, with money being used to support those who take an active part in commissioning.
'It might not happen initially, but there will be some element of pay that will be tied to commissioning,' he says.
GPC negotiator Dr Chaand Nagpaul says that, if the DoH insists on including commissioning in the contract, it should simply require GPs to consider the resources their patients are using.
'To expect every GP to be heavily involved in commissioning decisions is unrealistic,' he says.
Dr Jenner agrees and believes the new commissioning regime will require two contractual tiers. GP provider contracts could be changed to include 'resource utilisation clauses', as Dr Nagpaul says, and separate contracts could remunerate GPs who wish to direct larger GP commissioning groups.
GPs risk taking the blame for cuts that will be needed to balance the NHS books in future years, adds Dr Jenner.
Individual GPs could be derided for 'live or die' treatment decisions in the press or even blamed by future governments if the NHS is failing. 'Look at the Daily Mail headlines on NICE and cancer drugs. Who's next in line?' he says.
Dr Nagpaul argues that 'GPs are not managers' and that the statutory duty for commissioning budgets must remain with PCTs. The GPC wants GP commissioners to have an equal level of accountability as PCT commissioning staff have had.
'This should be no different to the accountability of NHS middle managers who have a salary that is unaffected by their commissioning decisions,' says Dr Nagpaul.
With SHAs due to be scrapped by 2012, and PCTs' commissioning duties taken away, the NHS is in line for yet another structural upheaval.
David Stout, the NHS Confederation's PCT Network director, believes the new independent NHS board is likely to hold GP contracts and then distribute and oversee the use of commissioning budgets.
But Dr Jenner thinks this aspect of policy 'doesn't add up yet'. 'There will only be four of these small regional offices in charge of 2,000-plus GP practices (each). That's not practical.'
Dr Charlson says PCTs will remain, if only to resolve tendering issues and provide administrative support.
The size and design of commissioning groups may vary. At this month's LMCs conference in London, King's Fund chief executive Professor Chris Ham predicted that the DoH's preference would be for networks of 'like-minded' practices forming groups rather than just neighbouring practices doing so.
'This would encourage competition and avoid local monopolies,' he told delegates.
So are GPs up for it? Just over half of delegates at this year's LMCs conference want commissioning responsibility.
Dr Jenner adds: 'Only about 5 per cent of GPs will take this up, but that will be enough.'
Mr Stout says that once GPs feel 'ownership' of commissioning, its popularity could flourish.
But remuneration and accountability are key issues the White Paper must address. If there's not enough to tempt GPs, phase two could be private firm-led commissioning.