The ability to get served in a busy pub is sometimes regarded, like changing a duvet cover, as one of the defining skills of adulthood and an unfakeable test of character.

The truth is less straightforward. Bar presence, or the lack of it, is a random mixture of looks, luck, persistence and, critically, the skill of the person serving. An alert bartender will clock you even if you’re wedged behind a big bloke and fiddling with your iPhone, while a less-bothered one can ignore you all night, no matter how much charisma you ooze.

Some of us are old enough to remember when the average bartender knew who was next in a mob of clamouring punters, while mentally totting up the price of ten different drinks and change from a doubloon. Such arithmetical talents were put out to pasture by the advent of tills that not only know the prices but also when the tonic’s running low and the state of the toilets. And that, you might think, should have left room for more engagement in the central task of punter-serving.

Happily, in some places the core skills of this venerable and complex profession are in fine form, and nowhere more so than at the superb Harp, in Covent Garden.

This national treasure of a pub, only a few yards from Trafalgar Square and the National Gallery, is usually packed, thanks to its impressive range of great ales and an atmosphere of joyful conviviality. But, while in some pubs popularity means a long wait for service, the Harp is also blessed by bar staff with eyes everywhere.

Ever-alert, swift and friendly, the staff at the Harp leave no punter behind and encapsulate all that’s best about their essential trade. And long may they do so, because bartending is of such immense social significance that it will still be a central part of life when changing a duvet cover is about as useful as yoking an ox.

The Harp, 47 Chandos Place, London WC2N. 020-7836 0291.

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