Bus services in Finglas in north Dublin have been curtailed because of increasing numbers of attacks on bus drivers.
Drivers say the attacks are happening two or three times a day and they are refusing to service certain areas after 7pm.
Dublin Bus and gardaí are running an information campaign to highlight the problem.
They have also proposed to increase security arrangements on the buses, including having uniformed gardaí travelling on board.
Drivers are voting today and tomorrow on these proposals. If they accept them, services will return to normal.
But they have warned that if these attacks keep happening, the curtailment of services will continue, and could possibly worsen.