The ecumenical movement, symbolized by the Greek term 'oikoumene' meaning 'entire, inhabited world', aims to create unity amongst the many denominations that make up Christianity.
Since 1054, the Christian Church has developed widely different practices and theologies due to the reformation and subsequent splintering in Protestantism.
The World Council of Churches first met in Amsterdam in 1948 with 351 delegates from 147 church bodies, defining itself as a 'fellowship of churches' and described by outsiders as an 'ecclesiastical United Nations'.
The Roman Catholic Church is not a member of the World Council of Churches, but it participates in two subgroups with full voting rights: The Faith and Order and World Mission and Evangelism Commissions.
The World Council of Churches defines its mission as 'visible unity of the Church' which includes striving for a common confession, sacramental life, mission and service.
Three main areas of work of the World Council of Churches are Unity, Mission and Ecumenical Relations, Public Witness and Diakonia, and Ecumenical formation.