The Stage reports that technicians' union BECTU and the Society of London Theatre will meet at conciliation service ACAS next week to discuss an ongoing pay dispute.
If the case is not settled, industrial action is a possible next step.
The union is seeking London living wage - £8.80 - for workers on three pay grades below that rate, and a 6 per cent rise for all other members.
SOLT's most recent offer was a 1.8% increase, which was overwhelmingly rejected by BECTU's membership.
Last year, BECTU and the Ambassador Theatre Group underwent successful conciliation at ACAS over changes to the pay offer.
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