The most popular ads are nearly always the old ones. In Channel 4's 100 Greatest Ads programme, Smash "Martians", Levi's "laundrette", R White's "secret lemonade drinker" and Hamlet "photo booth" were among the oldies that made it into the top ten.
Maybe it's not surprising, then, that clients are keen to fall back on this supposed golden age of advertising and use ideas, strategies and straplines that are regarded with such affection.
Last week, Guinness did exactly that. Its new poster campaign features the famous Guinness toucan in a style reminiscent of its ads from the 30s. And this is not the first time it has fallen back on old ideas.
The Guinness Extra Cold campaign adapted all of its old favourites, giving them a chillier feel. "Surfers" became "surfers' retreat", as the originally plucky group decide not to brave the freezing sea, "fish on a bicycle" was updated to feature the fish cycling in the snow and the crazily dancing man was made into an Eskimo.
But does the fact that Guinness' agency, Abbott Mead Vickers BBDO, had to recreate these ads mean that it failed to come up with new ones that were as good?
Mark Lund, the chief executive of Delaney Lund Knox Warren & Partners, says: "From the inside, the Extra Cold ads do feel like they have given up on anything new but, genuinely, people out there love them. The new Extra Cold property does give them a reason for being. The toucan smacks more of old ideas. I can't think that any current Guinness drinkers would remember that advertising."
Russell Jones, Diageo's marketing director, defends the move: "The toucan campaign is to tell drinkers that Guinness is moving all of its production back to its Dublin brewery.
"It's going back to its roots and it made sense to tell this story with an iconic advertising character."
He adds that there has been no conscious move to use past campaigns in all of its advertising, but admits the old campaigns work particularly well for the Guinness brand. "Guinness is steeped in history and tradition and its drinkers like it for this reason. They respond well to the old ads," he says.
As do most Brits, Rooney Carruthers, a partner at VCCP, argues. As a nation we love to reminisce and Carruthers says we warm to TV programmes and ads from our past. "I'd love to see some of the old PG Tips ads on again and I don't know why Levi's doesn't re-run some of its campaigns," he says.
Orange appears to be looking to capitalise on this nostalgia and, like Guinness, it is returning to its (more recent) advertising heyday. Although Orange and its agency, Mother, are keeping details under wraps, the mobile phone operator is said to be going back to a strategy that puts its much-lauded "the future's bright, the future's Orange" campaign idea back at the centre of its communications. The line was created by WCRS for Orange's launch 11 years ago.
New commercials, set to break later this year, are expected to focus on images of light and brightness, rather than on the pricing and deals on which its current campaign concentrates.
Lund believe this is a wise move by Orange, saying: "The idea of a mobile telephone being part of a bright and glamorous future, rather than the present grubby price wars, gives it an emotional high ground. It takes it out of the 'we'll give you more texts for less money' battle-ground that it's been stuck in."
John Webster, a former DDB London executive creative director, disagrees: "There was the possibility of an Orange future when it first came in, but not now. It looks as if they couldn't think of any-thing better."
With the company looking to reverse a 3.2 per cent UK revenue decline, it definitely needs to change its ads, however. The strategy that proved successful and attracted millions of users in the 90s is, at the very least, a proven option.
But is safe necessarily the best route? Smash reintroduced its Martians in the late 90s but failed to get the original cut-through. And, despite many in the industry feeling that the AA should bring back its "fourth emergency service" positioning, its ad agency (DLKW) thinks otherwise.
"It was a brilliant strategy, but now it's not applicable," Lund says.
"The perception of emergency and an emergency service has changed so much after 9/11 and terrorist threats that it's no longer credible that someone putting your car back on the road could be classed as an emergency service."
There is clearly the danger that an old campaign won't work in its new setting and that a line or an idea that once resonated with consumers will no longer be relevant.
The "Martians" campaign, for example, depicted characters in space, at a time when space travel was exciting and sexy. In the late 90s, this was no longer the case and the new commercials failed to make much of an impact.
Perhaps, then, taking the plunge with something new and wholly relevant to the here and now is the preferable route. Webster believes that it's admitting defeat to go back and thinks there is a need to move on and develop new ideas.
"The past is looked at through rose-coloured glasses. There always was a load of crap about too," he says, concluding: "We still have the talent capable of creating brilliant campaigns. We need to start making some new stuff."