Supermarket chain Asda will seek proof of age before selling alcohol to anyone who looks under 25 as part of a trial scheme in 10 Scottish stores.
A total of 10 Scottish Asda stores will trial the ID scheme
Alloa, Falkirk, Kirkcaldy, Grangemouth, Coatbridge, Cumbernauld, Dunfermline, Galashiels, and Chesser and St Leonards in Edinburgh are part of the plan.
The move follows research commissioned by the company asking shoppers to guess the age of a group of 16-year-olds.
It found that 71% thought they were over 18 and 23% put them at over 21.
A spokesman for the company said the scheme was "responsible retailing" and hoped to remove the stigma from requesting and providing ID.
The Challenge 25 initiative follows on from a Challenge 21 plan which Asda said would "empower" staff asking for proof of age.
"A mistake on guessing someone's age could mean a hefty fine and a criminal record," explained Asda retail director Andy Clarke.
"Challenge 21 helped make asking for ID in our stores less of a taboo but our research now highlights the need to go one step further in a bid to help protect our colleagues.
"Importantly, we also want to use this trial to call on other retailers to undertake their own trial as it's only when we act as a united industry that we can really make a difference to the impacts of underage drinking."
Louise Macdonald, communications director at Young Scot, praised the initiative.
"Any activity which promotes awareness and understanding about the issues around the sale of restricted goods such as alcohol is to be welcomed," she said.
Mr Clarke said he believed the plan would be welcomed by customers.
"For many this trial will require them to permanently carry ID," he said.
"However, we are confident that all of our customers who are lucky enough to look under 25 will understand the importance of this campaign, just as they did when we launched Challenge 21.
"What we want to see though is a culture in the UK where being asked for, and showing, ID isn't an issue - it's just responsible retailing."