Canon Kenneth Kearon is "delighted and honoured" at his appointment as secretary general of the worldwide Anglican Communion.
The first Church of Ireland member to hold the position he assumes office next January.
It was "a great honour for the Church of Ireland also," he said.
He will be based at St Andrew's House in London, from where he will perform "an ambassadorial role" to the Communion's 38 provinces, representing a population of 78 million Anglicans.
He will also represent the Communion at meetings of international bodies.
He believed his work with the Irish School of Ecumenics, of which he has been director since 1999, will be "very helpful" in this and the many international contacts he had made through it.
From Sandymount, Dublin, Canon Kearon was ordained in 1981 and served as curate at Raheny and Coolock before becoming dean of residence at Trinity College.
He was then rector in Tullow, Co Dublin, before being appointed to the Irish School of Ecumenics.
The Church of Ireland primate, Archbishop Robin Eames, said: "He brings to this key position in our worldwide family of churches many gifts and a rich experience of ministry.
"His ecumenical work has gained him great respect and at this time of serious challenge within the Anglican Communion he will be called upon to exercise widespread influence as we seek to build up relationships and trust in our diverse Communion."
The Archbishop of Dublin, Most Rev John Neill, said the news "brings great delight to the Church of Ireland, and in particular to the Diocese of Dublin, and Christ Church Cathedral of which he is chancellor".
The Most Rev Neill also said that Canon Kearon "brings to his new appointment to this very responsible international post for the whole Anglican Communion pastoral, administrative and academic gifts, coupled with wide ecumenical experience" .