Oilibhéar is a former principal of an Irish-medium secondary school in Dublin and before that he taught Irish and History at Malahide Community School, Co. Dublin. In more recent times he served as a Senior Inspector (post-primary) of Gaeilge with the Department of Education and Skills (DES) and was centrally involved in evaluation of management, leadership and learning at second level. As a Senior inspector he was closely involved with Irish-medium and Gaeltacht schools and specifically with the introduction of the Gaeltacht schools e-Hub Leaving Certificate Physics Pilot Project (2017 – 2022). He has extensive experience of the Irish education system having served as DES representative on a number of National Council for Curriculum & Assessment (NCCA) advisory committees. He currently delivers a module on management & leadership in Irish-medium and Gaeltacht education as part of the M.Ed. programme (M.Oid. san Oideachas Lán-Ghaeilge agus Gaeltachta) at Mary Immaculate College, University of Limerick.