The four "Instruments of Unity" in the Anglican Communion are, in historical order, the Archbishop of Canterbury, the Lambeth Conference (of Bishops), the Anglican Consultative Council, and the Primates' Meeting.
In addition, there are a variety of commissions, networks, consultations and other initiatives that have received recognition as "official" undertakings of the Anglican Communion.
The inter-Anglican budget is intended to fund all Anglican Communion activities on a communion-wide basis, including the support of the Anglican Communion Office (ACO), which acts as secretariat to all four Instruments of Unity. The ACO is centered on four main areas -- the work of the Secretary General, Communications, Ecumenism, and Mission and Evangelism.
Information on the Anglican Communion website is commended for further information and study (http://www.anglicancommunion.org).