Bogus traders and scam artists have been caught out in Powys by a new scheme alerting the public to anyone acting suspiciously.
Fake charity workers and a caravan thief are among those who have been arrested thanks to "ringmaster".
Messages about "sharp practices" are sent by trading standards officials to the scheme's 1,186 members by fax, text, e-mail or by telephone.
A survey has found that 94% of its members are satisfied with the system.
The project was created by Powys Council and operates from one of its offices in Brecon.
The local authority said its staff sent warning messages based on the intelligence and complaints they received.
Graham Brown, board member responsible for public protection, said: "By improving the flow of information between the council and police and the community, we can make a greater impact in the prevention and detection of crime and anti-social behaviour."
Clive Jones, the council's principal trading standards officer and manager of ringmaster, said: "Ringmaster messages are about sharp practices, rogue traders and marketing scams as well as crime-related matters."
Among the scheme's members are neighbourhood watch co-ordinators, farmers, national park officers, shop owners and businesses.