The National Gallery isn't broken, so don't try to fix it

'People have shuddered at the thought of the man responsible for the Mario Testino show taking over'

The National Gallery is quite unlike other similar museums and is a collection of unique quality. Most national galleries are primarily museums of the nation's art, but the British rooms at the National Gallery, although of stunning quality, are not its raison d'être. The English were, from a very early period, enthusiastic buyers and collectors of foreign painting, and the National Gallery is principally a museum of European old masters.

One of superlative quality, too. Other museums of international tendency, such as the Louvre or the Hermitage, may have much larger collections; museums that principally document the nation's art, like the Prado or the Uffizi, may cover a particular area in more detail. The National Gallery is unique because, from a collection of middle size as far as the great museums are concerned, it has a truly supreme example of almost every great painter.

It is the most concise history of Western painting in the world – there are no museums which can match the quality of the Pieros, the Raphaels, the Rembrandts, the Velazquez, the Hogarths and the Cézannes, although some can match or surpass the museum in any one of these. There are some gaps – for French rococo painting, you will need to head up the road to the Wallace Collection, and German painting in general is rather under-represented. But, in general, the lavish buying habits of the English over the centuries, and their wide and varied curiosity, have produced a national collection of remarkable consistency and value.

The move of Neil MacGregor from the National Gallery to the British Museum, and his replacement with Charles Saumarez-Smith of the National Portrait Gallery, is a good moment to consider the nature and direction of the gallery. In general, MacGregor has been perceived as a highly successful director, and there is no reason to dissent from that. These days directors of museums are principally judged on the success and interest of their temporary exhibitions. MacGregor has done rather well, I think.

His exhibitions on themes, or individual artists, have very often been both extremely interesting and highly popular. Shows on Dutch subjects have always been excellent, typified by the ravishing Aelbert Cuyp exhibition now on; shows with a Delft or a Utrecht theme were memorably intelligent and informative, too.

It's the consistent intelligence and seriousness of MacGregor's temporary exhibitions which have made people wonder about the suitability of Charles Saumarez-Smith. Certainly, the NPG's exhibitions in recent years, although often very successful, have not had anywhere near the intellectual gravitas. He has run the NPG in a very efficient way, true, but many people have shuddered at the thought of the man responsible for the current nullity that is the NPG's Mario Testino show taking over in Trafalgar Square.

Temporary exhibitions, however, are not the whole of it, and a more important expression of a director's responsibility lies in the issue of new acquisitions. Acquisitions in the gallery's central areas of interest have become almost inconceivable in recent years, apart from through the occasional bequest or long-term loan. Many of the areas in which the gallery is currently rather thin will now remain so; it is not likely that the gallery will ever be in a position to expand its French 18th-century holdings to any significant extent, for instance.

But it would be nice to think that a far-sighted director will be able to start acquiring paintings with intrinsic merit before the rest of the world wakes up to them. Michael Levey's period as director is remembered for his impressive acquisitions, and it is disappointing that MacGregor's reign, under very different circumstances, has only occasionally produced a real rabbit out of the hat. It would have been nice if MacGregor had been able to back his enthusiasm for 19th-century German painting with the acquisition of an Adolph Menzel; he is as interesting as Manet, and a much more affordable painter as yet.

And there are areas a determined director could exploit, and entirely change the complexion of the gallery. It's wonderful to see a great interior by Vilhelm Hammershoi in the collection now, and a director with a sense of purpose could create an impressive Scandinavian room for which future generations would thank us; the reputation of the school is on the move, but they are not yet beyond the gallery's budget.

The key point, however, is that what the National Gallery has, and what it can go on supplying, are resources of incalculable worth, enormous experience and learning. If Saumarez-Smith has any sense, he will continue the atmosphere of high seriousness, commitment to instruct, and devotion to artists and subjects that are not necessarily the most celebrated or popular. He is an intelligent man, and ought not to listen to anyone proposing updating or jazzing up. As they say; if it ain't broke, don't fix it.

hensherp@dircon.co.uk