A generation ago if you needed medical attention outside surgery hours you would almost certainly be visited at home by your GP or one of their partners.
Two or three years ago, you might have been asked to attend a primary care centre run by a GP co-operative or be visited by a doctor employed by a commercial deputising service. Today, you could ring NHS Direct or visit a walk-in centre and see a nurse.
Tomorrow, who knows?
The menu of choices may make it easier to get care, but there is concern about the consistency of advice and about the cost of providing services with so many overlaps. Earlier this month health minister John Denham announced a review of GP out-of-hours arrangements, looking at whether services are clinically effective, good value and responsive to people's needs - and how they can be integrated with NHS Direct.
Nigel Edwards, director of policy at the NHS Confederation, says: 'There is a clear agenda - the government is trying to increase the consistency that the system offers to patients.'
Part of this may be cost-driven: Mr Edwards suggests that different parts of the system giving conflicting advice will lead to greater demand, and it is obviously a waste of resources to have patients triaged twice - once by NHS Direct and then by a GP co-op or deputising service. But integrating services treads on professional toes.
The British Medical Association's GPs' committee is certainly suspicious of NHS Direct and says it is as yet unproven. There is also opposition from grassroots GPs, who see it as something foisted on them without consultation or involvement. But many GPs have already moved towards providing out-of-hours care through a cooperative where the duty doctor is unlikely to know the patient's history.
Nurse involvement is also becoming more common: around 20 per cent of GP co-ops already use their own nurses to triage calls for duty doctors, and triage has become more common in daytime surgeries. It is also used by some commercial deputising services.
These trends may make GPs more willing to accept nurses filtering patients. Some co-ops are already using NHS Direct nurses to triage their calls - the Harmoni co-op in West London, for example, takes all its calls through NHS Direct.
But the structure of NHS Direct may make this harder to replicate nationwide. The government is likely to opt for a 20-centre model, making it unlikely that NHS Direct call centres and GP co-ops are coterminous.
Local doctors may also want different protocols used to filter patients, while NHS Direct is committed to one standardised system.
In an increasingly web-literate society, e-NHS Direct may also have a role.
Patients could be directed to other forms of care or given reassurance and self-help advice through interactive computer programmes. But this is unlikely to reach groups who find it difficult to access the NHS in the first place, such as those in poverty or without computers.
How far NHS Direct will replace GP organised cover is debatable. National Association of GP Co-operatives chair Dr Mark Reynolds is hopeful it may triage for co-ops and remove a significant percentage of the cases of selflimiting illness - but he points out it handles far fewer calls than the GP system and would need to increase its capacity.
GPs' committee negotiator Dr Laurence Buckman says: 'There is certainly a view within parts of government that NHS Direct should be delivering all the services out of hours.'
One scenario, then, would be GPs ditching their 24-hour commitment and instead voluntarily contracting to provide medical care to patients preselected by NHS Direct.
Professor John Nicholl, director of the medical care research unit at Sheffield University, goes further. He suggests splitting services between chronic diseases, ongoing treatment and urgent care, regardless of the time they are needed. 'NHS Direct and GP co-operatives both provide these immediately necessary services - but why is it only out-of-hours?'
Walk-in centres in major cities are also changing the way patients access care by opening until late in the evening. Inevitably, they will be used by some people as alternatives to their GP's out-of-hours cover, but Dr Reynolds believes their effects will be marginal. They could also carry a sting in the tail for the government as the cost of providing 'routine' services for 16 hours a day may be prohibitive.
A growth in the number of minor injury units, open until mid or late evening, is also likely to affect patients' perceptions of where they can access treatment.
Many primary care trusts may commission units in community hospitals - especially if accident and emergency departments become more centralised - but they are also increasingly used alongside casualty departments to siphon off the 50 per cent of patients who do not need the full resources of A&E.
There may be opportunities for GP co-ops to work more closely with minor injury units, possibly sharing sites and even staff. 'The distinction begins to blur between minor injury units, out-of-hours centres and walkin centres, ' says Dr Steve Gillan, director of the primary care programme at the King's Fund.
A call to NHS Direct costs the NHS£8, which is less than the cost of seeing a GP out of hours or visiting an A&E department. 'But the question is whether it is offering value for money and whether it appropriately diverts patients from misuse, ' says Dr Buckman.He suggests that patients are still going on to contact their GP.
Rationalisation could be hampered by the different funding streams: minor injuries units are often run by community or acute trusts, for example, while GPs' out-of-hours payments are determined through their terms of service.
PCTs may be best placed to push forward integration as they are likely to work closely with GP co-ops while also commissioning other services. But concerns about continuity of care in a system with so many different entry points will be hard to overcome. An electronic patient record accessible by healthcare professionals across the system would be one solution, but is a long way off.
With the government committed to access for all, the future shape of services is likely to vary across the country.
While walk-in centres may increase access in central London, they will do little for rural Northumbria or Devon.
However, NHS Direct could help rural GPs - who often can't join co-ops and have to do their own night calls - by triaging.
But one thing seems certain: the enormous political capital being invested in NHS Direct makes it a strong contender to be a major player in whatever permutation of services emerges.
Out of hours - the patients' view The 1998 National Survey of NHS Patients found:
14 per cent of those registered with a GP had made an out-of-hours telephone call to their GP surgery or to a central out-of-hours number, within the past year;
43 per cent of these received a visit from a doctor (either their own or a locum);
50 per cent of those who received a visit had to wait less than an hour;
22 per cent reported waiting two hours or more;
20 per cent of callers were given advice over the telephone;
16 per cent were asked to visit their surgery when it opened; 14 per cent were asked to go to their nearest A&E.
These patients were less likely than others to be satisfied with the response to their outof-hours call.