And how are the GPs doing?

We take our GPs for granted. It is not just that we expect them to be there on tap, reliable, proficient, sympathetic, free - expectations that these days increasingly seem frustrated. We also assume that there is something right and natural about the very existence of the family doctor as first port of call, providing a full range of primary care and giving us access to specialists and hospitals.

Yet the plain truth is that our general practitioner set-up, with its associated referral system, is very much the exception among leading industrial nations - France and Germany do not have it, nor does the United States (though family medicine as a speciality has been growing there in recent years). This fact provokes two questions: how is it that we have - or better, perhaps, still have - the GP system? And, is it a system that, if we cast aside our sentimental Dr Finlay-type attachments, actually delivers high-quality medical care? These are the key issues addressed by the 14 contributors to this stimulating and scholarly collection published to mark the half centenary of the National Health Service.

It should come as no surprise that, in large measure, it was the advent of the NHS that, despite initial virulent hostility from the British Medical Association, enabled general practice to survive, indeed made the GP available for the first time to the entire population. Had Aneurin Bevan attempted to replace the traditional "cottage industry" GP - still, in those days, chiefly a one-man practice, operating from home - with, for instance, salaried medical care under local authority control, the ensuing revolt of rank-and-file doctors would instantly have scuppered the scheme. In most respects, Bevan's adroitness proved advantageous. The nation got access to competent health care, free at point of service; and, underwritten by the state, the general practitioner was able to soldier on.

But, as several of the authors insist, there were costs as well as benefits. The typical GP was under-resourced and under-skilled; the service as a whole was allowed to stagnate in a postwar world in which medical progress was identified with big and gleaming hospitals. The 1950s brought numerous exposes of filthy surgeries without so much as running water, and lacking diagnostic equipment beyond a stethoscope.

The revitalisation of general practice from the mid-1960s is plotted in several essays: Kenneth Robinson's Family Doctor Charter in 1966; the growth of health centres, well-equipped and supplied with ancillary staff, the new patient-oriented psychological approaches evangelised by the inspirational Michael Balint, the erosion, albeit slowly, of traditional divides and suspicions between the GP, public-health medicine and the specialist elite. Some authors hint at an ensuing "golden age" of general practice from the mid-1960s to the mid-1980s, until financial stringency and then the market-driven philosophy of the Thatcher and Major administrations put GPs under pressure and once more challenged their professional status.

Some patients (particularly the old) cling to the ideal of the familiar family doctor, while others simply want the best treatment. In these circumstances it is natural that some contributors envisage a vital future for the GP as the provider of personal care, whereas others view the beast as a fortuitous survival, destined for extinction amid modern high-tech, high-cost medicine - or at least, if surviving, doing so only by evolving into something quite different.

What is clear, as Marshall Marinker shows in a characteristically penetrating piece, is that it would be a mistake to separate the modes of medicine that are practised from the personnel who are practising it. If we were to replace the GP system, we would also have to change our very notion of what medicine is about. We lose sight of that fact at our peril.

Roy Porter is professor in the social history of medicine, Wellcome Institute.