The stores in the Upper Gornal and Castle and Priory wards of the town agreed to sign a voluntary code of conduct to help stop under-18s getting their hands on alcohol.
In return, police have been offering staff advice on how to protect premises against theft and how to deal with gangs of youths congregating outside shops.
Sgt Natalie Hobster, one of the officers who set up the scheme, said she was pleased so many retailers in the area were backing it.
"It's us saying, 'look, we are asking a lot of you, but we are trying to support you too'. It's a way of tackling under-age drinking together," she said.
Shops are also being hooked up to a radio network with the police which enables them to share information about persistent under-age youths trying to buy alcohol and Police Community Support Officers make regular visits to check there are no problems.
Hobster said: "We will review things in three months' time, but so far we are really pleased. I was a bit nervous and sceptical that it would work at first, but we've had a fantastic response."