Pickets are being placed on the Tyndall Institute attached to University College Cork today.
The Irish Federation of University Teachers and SIPTU are mounting the pickets in protest at pay inequality between staff at the Tyndall Institute and counterparts in UCC.
They are in place until 6pm today and next Wednesday they will spread to the wider UCC campus.
Louise O'Reilly, the Sector Organiser for Education with SIPTU, says the pay difference is up to 20%.