Up to 15 ESB network technicians, who are members of the Independent Workers' Union, are on the picket line outside ESB offices at The Basin, Tralee today.
The union says the dispute is about the failure of the ESB to partake in any meaningful discussions in relation to outsourcing its members' work to third parties.
The union, which represents over 500 technicians, says it remains available to enter talks.
ESB Networks says the 24-hour action is unlawful and is threatening legal action; it does not recognise the union.
Kerry Sinn Fein TD, Pa Daly, spoke with workers on the picket line in Tralee this morning.
Deputy Daly said all workers in the county have concerns about outsourcing and is calling for all parties to engage on the issue: