A worldwide convocation of bishops from across the Anglican Communion that meets once every ten years under the presidency of the Archbishop of Canterbury. Named the Lambeth Conference after Lambeth Palace, the venue where the earliest meetings were held. (Although the most recent Conference of 1998, was held in the more practical enviroment of the University of Kent in Canterbury.)
The first conference was held in 1867 to settle a theological dispute between the bishop of Capetown and the suffragan bishop of Natal (the later had apparently questioned the truth of the Old Testament). The latest was held in 1998 and rather famously decided (amongst other things) that homosexual practice was incompatible with scripture.
The conference itself has no legislative authority over the national churches that compose the Anglican Communion and has no power to bind any bishop to the resolutions it adopts. All the reports and resolutions considered are merely advisory and are seen as merely influencing opinion within the worldwide church.
Sourced from http://www.archbishopofcanterbury.org/ and http://www.lambethconference.org/