1. Robert Hill
Number 10 policy unit adviser on health
10 Downing Street
"We don't release information about Number 10 staff." The government is not required to tell us anything about the most powerful individual in the NHS.

What we know is that he is a former theology student, one-time binman, National Union of Public Employees officer (he was active in the 1982 NHS strike, the longest in health service history), and Labour Party official. Joined the Downing Street policy unit team in May 1997. He is Tony Blair's trusted advisor on health. "Blair and Hill share the same core beliefs on health," says one insider.

Credited with coming up with initiatives such as NHS Direct and walk-in centres, and establishing a Daily Mail-friendly "safety first" approach to mental health policy, to the horror of the clinical establishment.

He is Blair's emissary to the Department of Health (DoH), where he delivers high-voltage news of his master's dissatisfaction, and reputedly has the power to make or break ministerial careers.

Quiet, intelligent, and regarded by some as aloof and pompous. "When I knew him he was called Bob, and now its Robert," says one former union colleague. But no one questions his power. "If it (a health policy idea) doesn't fit in his world view, it's unlikely to happen," claims one observer.

2. Nigel Crisp
NHS chief executive
NHS.uk
Chief executive of both the NHS Executive and the DoH. The first NHS chief to combine the two posts, and therefore the first NHS chief with a seat among the power brokers at the civil service top table. Widely respected in the NHS management community, he arrived in his present job after the launch of the NHS plan, but responsibility for its implementation lies in his hands.

3. Sir George Alberti
President, Royal College of Physicians
Royal College of Physicians
Blair's modernising representative on Planet Consultant. Plugged into the higher level medical power networks, although his influence stretches further afield: he helped draw up the national health framework on coronary heart disease, sits on the NHS modernisation board, and advised ministers on the appointment of Nigel Crisp as NHS chief executive.

4. Simon Stevens
Head of the strategic policy unit, Department of Health
Department of Health
Career NHS manager turned policy advisor to both former health secretary Frank Dobson and incumbent Alan Milburn. The latter created a strategic policy unit in the DoH (possibly to counterbalance the influence of Number 10 and the Treasury), and made Stevens head of it. Worked closely on the NHS plan, now looking at health policy options for a second term of Labour government.

5. Professor Liam Donaldson
Chief medical officer for England and Wales
DoH Chief Medical Officer
As the holder of the top doctor's post in England and Wales he is the clinical face of the DoH, and has immense influence on key public health issues (as the recent Phillips' report on the BSE crisis, which examined the role of his predecessors, made clear). As chief medical officer to the government, not just the DoH, he has serious reach across Whitehall, while his experience as a senior NHS manager gives him credibility in the NHS.

6. Professor Mike Rawlins
Chair, National Institute for Clinical Excellence
National Institute for Clinical Excellence
Respected pharmacologist who brings clinical credibility to the job of deciding which drugs and treatments are cost-effective enough to be made available on the NHS. If he can withstand furious counter-attacks from an outraged pharmaceutical industry lobby and the right-wing press (witness the furore over flu drug Relenza), he will have immense power to shape NHS clinical practice and investment decisions.

7. Alastair Bridges
Head of Treasury health team
HM Treasury
The Treasury is increasingly influential on health policy, imposing the financial and performance framework in which the NHS operates, and - according to its critics - micro-managing the NHS in an unprecedented way. It holds the purse strings, and has a major say in the development of new hospitals and GP health centres. As head of the health team, Bridges is a key figure, visiting trusts and health authorities as the Treasury's very own NHS productivity inspector.

8. Chai Patel
Chief executive, Westminster Health Care Holdings plc
Labour party donor, Blair favourite, and head of one of the UK's biggest private healthcare providers. Persuaded the government to use private care homes to provide intermediate care for NHS patients. Influence also over long term care and social care policy through his many government committee appointments, including the NHS older people task force and the Cabinet Office better regulation task force.

9. Ian Bogle
Chair, British Medical Association
BMA Online
Experienced medico-politician. Although he has signed up the BMA to the principles of the NHS plan, and sits on the NHS modernisation board, his organisation's commitment to NHS reform is always conditional and self-interested. Bogle's position gives him the power to stall the government's ambitious project should his members revolt over plans to tighten regulation of doctors, or limit consultants' private earnings.

10. Paul Dacre
Editor, Daily Mail
Daily Mail
The Mail's tales of impending NHS collapse are read and possibly believed by the millions who reside in that virtual geographical space known as middle England. Not the obvious newspaper of choice for NHS policy makers but its sallies into the healthcare arena cause tremors in the corridors of the DoH in a way that no other national media outlet can.

11. Peter Homa
Chief executive, Commission for Health Improvement (CHI)
Commission for Health Improvement
Respected career manager and former head of government waiting list taskforce, now in charge of the nascent regulatory body aimed at driving up standards of NHS care. Initially likely to adopt a "softly-softly" approach to inspections in a bid to shrug off CHI's "Ofsted of the NHS" reputation, but its wide powers to investigate failing hospitals and monitor quality gives CHI real muscle.

12. Stephen Thornton
Chief executive, NHS Confederation
NHS Confederation
Articulate spokesman for NHS management with a high media profile. Has turned the confederation into a highly effective lobbying machine. An influential contributor to the NHS plan. He sits on the NHS modernisation board, while his key managers colleagues sit on modernisation task forces.

13. Professor Chris Ham
Advisor, strategic policy unit, DoH
Health Services Management Centre
Health policy heavyweight who has influenced DoH thinking under this government and its predecessor. Currently a member of the DoH strategic policy unit set up to advise Milburn on the NHS plan and the direction of the NHS under a second term. Also director of the health services management centre at Birmingham University.

14. Christine Hancock
General secretary, Royal College of Nursing
RCN site
Head of what is potentially Britain's most powerful health lobby, with around 260,000 of the public's favourite health workers in membership. Any NHS reforms must get the RCN on side - Hancock was a key figure in helping Milburn firm up the NHS plan. Opinion is divided on whether Hancock has exploited nurses' leverage to the full, particularly over pay.

15. Bob Abberley
Head of health, Unison
Unison
Experienced trade unionist who helped ease Unison's access back to the corridors of power after years of being frozen out under the Conservatives. Milburn's link to the NHS rank and file. Influential on NHS human resources policy, but has failed to break Labour's love affair with the private finance initiative.

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