Officials in Dublin's local authorities are joining forces to identify and prosecute the people who put up posters around the city offering jobs which pay £20 to £30 an hour.
Dublin Corporation, Dun Laoghaire-Rathdown, South Dublin and Fingal county councils are chasing agents for what they believe is a British company.
The agents have been putting up on lamp-posts illegal posters advertising for staff.
The laminated posters are usually put up at crossroads. They say: "Earn £20-£30 per hour. Part- or full-time. Hours to suit", along with a contact number.
Mr Tom Casserly, litter warden, South Dublin County Council, said putting up unauthorised signage was illegal under Section 19 of the Litter Pollution Act.
Putting up each poster could result in a £50 fine, which, if unpaid, could result in court proceedings and a further fine of up to £1,500 for each poster.