The four-week, £250,000 'Responsible Alcohol Sales Campaign' is funded by the Home Office and intended to reduce alcohol-fuelled anti-social behaviour and violence.
Plain-clothes police officers will visit premises with a history of alcohol-related crime and disorder to clamp down on underage sales and ensure that alcohol is not sold to customers who are already drunk. The campaign will also target proxy sales.
A similar campaign has been launched in Scotland, where police have deployed 16-year-old volunteers to test stores across the country.
"Responsible licensees have nothing to fear," said justice secretary Kenny MacAskill, "but those who flout the law will face tough action. Losing their licences and substantial fines are both options."
Lothian and Borders assistant chief constable Ian Dickinson added: "We are aware that staff can find themselves intimidated by youths who attempt to purchase alcohol, and forces are keen to offer support in this regard."