More Carling is drunk in pubs than any other alcoholic drink. Richard Ehrlich explains why

When the UK makes the bold leap into 24/7 drinking, large numbers of us will be staggering home with a bellyful of Carling Black Label. Carling has been the nation's best-selling beer since the 1970s. Among UK lagers it has 22 per cent of the market, well ahead of Fosters (16 per cent) and Stella Artois (15 per cent). And the company doesn't plan to let the competition catch up.

Carling began life in Ontario, Canada, in 1840, grew rapidly, and entered the lucrative US market 40 years later. After the end of Prohibition it introduced the Black Label brand, a low-priced lager that was to make its fortune. Its commercial history is complicated, but there is one key fact to remember: international beer brands are almost always licensed by the parent company for brewing in individual markets, sometimes by companies that would be considered rivals, and their success in their native land is irrelevant in the global scheme of things. Few brands illustrate this better than Carling. A declining force in the North American markets, it has grown massively overseas. That growth has continued in the UK since the acquisition of Carling by the American brewing giant Molson Coors in 2002.

Carling Black Label is nothing more or less than a mainstream lager of sound quality, designed for drinking very cold. No beer aficionado would place it in the first division, but that isn't the point. Its success has always depended on good advertising and marketing. In the UK, domination has been achieved through a crafty combination of very appealing advertising (who doesn't remember "I'll bet he drinks Black Label"?) and well placed sponsorship.

Paul Hegarty, Coors's UK head of communications, explains the company's marketing strategy as aimed at capturing legal-drinking-age males aged 18 to 25 - and keeping them. "Once 'new recruits' establish their preferences, they tend to remain loyal. So it's important to have an intrinsically good beer which beats the competition in blind tastings. But quality isn't enough. It has to be driven by consumer insight. As far back as the 1980s, we spotted two important trends: the move to lager, and the increasing popularity of drinking at home. We realised that we had to have imaginative activities to make the brand attractive."

Sponsorship plays a large part. Carling sponsored the Premier League in the 1990s, and Hegarty says it is still associated with that deal even though it is no longer a sponsor. It sponsors a whole slew of English football clubs, and is breaking into the Scottish market with Glasgow Rangers. It sponsors the Reading and Leeds music festivals, and is "pouring sponsor" at a number of high-profile music venues.

Hegarty is clear about the brand's ambitions. Carling is sold in just under 40 per cent of pubs, and it sees that figure ("unusually low for a brand leader") as a golden opportunity for further conquest of the lager-loving hordes. "With a big brand, you have to keep it fresh. You can't stand still. You have to make it attractive to new drinkers without alienating existing customers." Given their track record, it doesn't look as if Carling will have any problems doing just that.

Top Tipples: What we drink the most of

Bell's The market leader since the 1970s, though Famous Grouse has been nipping at its heels. Old-fashioned, and reliable year after year. Owned by Diageo.

Gordon's Hero of 1,000,000 suburban drinks parties, survivor in the gin wars even after lowering its ABV to 37.5. Others lead in quality and ABV. Diageo owned.

Smirnoff Yanked from its Russian roots, invigorated in the US to become top of the heap where it remains despite fierce competition. Owned by Diageo.

John Smith's Extra Smooth The beer cognoscenti wouldn't look at it, but Scottish Courage must be doing something right: this is our best-selling bitter. Designed for serving at a low temperature.

Bacardi Superior So well known that many drinking it don't know it's rum. Aficionados know that there are dozens of better quality. The rum-and-Coke crowd couldn't care less. US-owned.