From the ACO’s Anglican Covenant page:

“The 1978 Lambeth Conference called for the creation of an Inter-Anglican Theological and Doctrinal Commission, and this commission in 1986 produced a report, “For the Sake of the Kingdom.” The 1988 Lambeth Conference called for a “common declaration” that would assist a coherent doctrinal identity for the Communion. While this was never agreed or adopted, there are some echoes of this call in the 2004 proposal of the Windsor Report (paragraphs 113-120) that provinces should bind themselves to each other by an inter-Anglican covenant.

“The Joint Standing Committee of the Primates and of the Anglican Consultative Council commissioned a study paper on the idea in March 2005, Towards an Anglican Covenant. At its meeting in May 2006, the Joint Standing Committee asked the Archbishop of Canterbury to establish a Covenant Design Group to further the project.

“Following considerable discussion and after circulating three drafts, this text was presented to the Standing Committee, which has approved it for distribution. In 2010, it was sent to the Provinces of the Anglican Communion for formal consideration for adoption by each Province through appropriate processes.”

By November 2014, 14 provinces had responded (12 affirmatively and 2 negatively). No further responses have been received. The Covenant project appears to have stalled.