sentences:  In 2009–10 he was the second Senior Advisor on Power-Sharing in the Standby Team of the Mediation Support Unit of the Department of Political Affairs of the United Nations.O'Leary is the author of numerous influential books about the Northern Ireland conflict, many of them co-authored with John McGarry, whom he met when they both attended Saint MacNissi’s College.McGarry and O'Leary's "Policing Northern Ireland