Shopkeepers in Crickhowell will be 'boarding-up' their windows on Saturday afternoon, as they continue their protest against plans for a High Street supermarket.
They plan to cover their windows with cardboard and brown paper, and write slogans like "closed" and "out of business due to supermarket".
Those involved say they want to give people an idea of what their High Street could look like if plans to build a 7am to 11pm convenience store go ahead.
Today's action comes after protests on the high street earlier this year, where more than a hundre people turned out to voice their opinions.
The planning application will be decided by the Brecon Beacons National Park.