Ground Floor: With a batch of young teenagers arriving at the house for a summer party, I high-tailed it to the supermarket to buy some soft drinks. Although I loaded up the trolley with juices and water, I knew that the main fizzy drink they'd want would be coke.

Obviously the drink is technically called cola but in most people's mind it's the same thing, thanks to the massive brand that is Coca-Cola, named last week for a fourth consecutive year as the world's top brand with an estimated worth of $67.5 billion (€56.1 billion).

This is good news for the company, which has underperformed while trying to update its products for evolving tastes. Coca-Cola knows that changes are fraught with peril, as it found out back in 1985 when, after a $4 million spend on testing the market, it introduced New Coke to almost universal disdain. Three months later the old formula was back. Following that debacle, the strategy has been to introduce variations on the theme such as Diet Coke and Coca Cola Zero but not to mess with the main iconic brand. In order to maintain its position at the top of the Superbrands table it spent $1.2 billion on marketing last year and expects to spend an additional $400 million this year.

Coca-Cola is a global brand phenomenon. The latest annual report shows that worldwide volume has grown by 5 per cent, cash from operations has increased 20 per cent and second quarter earnings per share were reported at $0.72 compared with $0.65 for the same period last year. Much of this increase, though, has been due to success in emerging markets like China, Russia and eastern Europe, while traditional markets have declined or remained static.

The company is also reassessing its advertising, which the chief marketing officer, Chuck Fruit, has admitted is "inconsistently effective". The company suggested that 2005 would be a "transition year" as it tries to balance sales of new "healthier" products against the desire of consumers not to change the high-sugar traditional products. Despite differing performances in different markets, Coca-Cola is still a good deal ahead of the number two company, Microsoft, which has a brand value of $59.9 billion.

The concept of the global superbrand has become more and more important to manufacturers as they fight for dominance in the world marketplace. The only two non-US companies in the top 10 are Nokia (number six) and Toyota (number nine).

Many different books and studies have looked at the phenomenon as researchers try to find out what it is that triggers us into buying one brand over another. But the general agreement seems to be that a superbrand has an emotional or physical advantage over its competitor and that consumers want and recognise this and are willing to pay a premium for it. Certainly it was the emotional attachment that consumers had to "old" coke which caused the hostility to "new" even though in blind tests many preferred the changed flavour.

The Superbrands Council in the UK has undertaken significant research into the area of branding and premium products and has concluded that consumers are generally willing to pay a premium for a high-quality brand, although less willing to pay a premium for a service industry. A sizeable number of consumers will continue to buy the same brand regardless of price and promotions (30 per cent in the case of food and drink and 24 per cent in the case of banking and financial services though I can't help feeling that in the case of the latter it's inertia, not loyalty).

One of the easiest ways to attract consumer attention is to offer something for free, or to price-promote, but the fact that price promotions do not necessarily sway consumers is something that the PR and marketing departments need to consider. Which is, presumably, why so many advertisers bombard us with lifestyle ads which are meant to evoke an emotional response to the people in the advertisement but not necessarily the product.

According to Jacqui Hill, who is on the Superbrands Council, marketing has become a "labour of love" rather than simply throwing money at reaching a mass audience. Paul Geddes, another council member, suggests that the strategy is to win on the things that work, save on the things that don't.

His advice is sound for anyone with a product to promote, but the difficulty is in blasting through the consumer affinity to one product and redirecting it towards your own. There is also the knowledge that Coca-Cola, for example, is over a hundred years old by now and has had a long time to imprint itself, not just on the minds of potential consumers, but on the minds of their parents, grandparents and great-grandparents, too.

There are, of course, short-term marketing blitzes and opportunities for faddish products (usually toys or gadgets that blaze a trail of glory one year and die, dusty and forgotten, the following one), but the true marketing guru will spot the difference between a company that has a long-term strategy and one which just wants to grab what it can today and let someone else be the true superbrand of the future.

In the modern marketplace it is easy to be a one-year wonder but not so easy to adapt to a changing market without losing your core customers - as so many leading companies have found. Creating a superbrand is not just about creating that emotional attachment for the consumer, it's about holding on to it, nurturing it and making the consumer feel good for sticking with your product.

Coca Cola presses all those buttons. Which is why, despite the fact that I can't drink the stuff myself, I was loading the trolley with it last Saturday.