The "London's Biggest Round" and "The North's biggest round" campaign, created by LoewyBe, will see a team of 130 uniformed brand ambassadors visit 4,000 outlets within the M25 for 10 weeks from mid July.
The campaign will urge drinkers to add Fosters, Kronenbourg Blanc, John Smiths and Strongbow to their rounds in a joint brand experience, which will target almost a million drinkers.
LoewyBe staff will invite people to trial a Scottish Courage brand free on pre-advertised promotion nights in participating outlets.
Drinkers will be encouraged to try the brand the following week by using a £1 money-off voucher, presented to them with a postcard directing them to a campaign where they can win brand-related prizes.
Tim Seager, marketing director at Scottish Courage, said: "This is much more than a mass sampling operation. Our 'Biggest Round' campaign is a tailor-made marketing initiative that will 'interrupt' drinkers' lives and actively engage them with our brands.
"It will provide a platform for one-to-one dialogues with up to a million consumers in a pub environment, giving us the chance to create countless new advocates for our brands. In return, consumers will be given a unique opportunity to appraise our market-leading beer and cider brands in a considered and responsible manner."
The activity will be supported with point-of-purchase support, including branded glasses, posters, flyers and back-bar displays.
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