The traditional date for the annual Week of Prayer for Christian Unity is January 18 - 25, to cover the days between the feast of St Peter and the feast of St Paul. We encourage you to use the official resource material for various opportunities throughout the year to express the degree of communion which the churches have already achieved and to pray together for that full unity which is Christ’s will. See also “A Select Bibliography of Catholic Documents and Statements on Ecumenical and Interreligious Relations” especially “Joint Declaration on the Doctrine of Justification” and also “Evangelicals and Catholics Together: The Christian Mission in the Third Millennium”
There are two sets of ecumenical guidelines which may be of interest.
Official Catholic ecumenical resources are available from the United States Conference of Catholic Bishops Publishing Office
www.usccb.org
Ecumenical resources from the Massachusetts Council of Churches are available here
www.masscouncilofchurches.org