BBC Wales members of the media and entertainment union BECTU have begun a 24-hour strike in protests at plans to make four editors redundant.
The strike, which began at 3am today, will affect the BBC's offices in Cardiff, Bangor, Abersystwyth, Swansea, Upper Boat, and Wrexham.
BECTU said it was 'convinced that redeployment opportunities can be found'for staff that face losing their jobs.
'In what is now a protracted dispute, talks have continued with management but these have failed to deliver concessions sufficient to resolve the disagreement,'said BECTU.
'An earlier notice of strike action was served but this was withdrawn to allow talks to resume. The union's mandate to take action short of strike was activated on 1 September."
Commenting on the dispute, BECTU's national official for Wales, David Donovan, said: "Our members are disappointed at the lack of progress despite the continued talks. Strike action is the last resort but we are now preparing for this."
A spokesperson for BBC News said: "Considering BBC Wales' record of successfully redeploying as many staff as possible, we are disappointed that BECTU has decided to take this action and apologise to our audience for any disruption to services this may cause. We are utterly committed to working with all individuals at risk of redundancy to seek out alternative employment."