The full version of this report (including footnotes) can be downloaded here in PDF format. Introduction: the development of the Anglican debate about same-sex relationships since 2000. In my previous roles as the Theological Secretary of the Church of England's Council for Christian Unity and Theological Consultant to its House of Bishops and in my current role as the Academic Consultant to the Church of England Evangelical Council, I have been tracking the development of the Anglican debate about same-sex relationships over the past fifteen years. During that time the focus of the debate has kept moving. When I started working at Church House, London, in 2000 the focus of the debate was still on the issues that had been discussed at the 1998 Lambeth Conference, namely whether it would be right to offer some form of blessing to same-sex relationships and whether it would be right for those in a same-sex relationships to be ordained as Deacon or Priest. In 2003 the election and subsequent consecration of Gene Robinson as the first Anglican bishop in a same-sex partnership moved the debate on to the question of whether it was right for those in same-sex relationships to be appointed as bishops (a debate that was also raised in a Church of England context by the proposal to appoint Jeffrey John as the Suffragan Bishop of Reading). Post 2003 the blessing of same-sex relationships and the ordination of those in same-sex relationships as Deacons and Priests has become a fairly frequent occurrence in large parts of The Episcopal Church and the Anglican Church of Canada and in 2010 Mary Glasspool became the second bishop in a same-sex partnership to be consecrated in the Anglican Communion when she became a Suffragan Bishop in the Diocese of Los Angeles. However, since 2010 the focus of the debate has moved on again with the new focus being on the issue of same-sex 'marriage.' With an increasing number of countries beginning to permit civil same-sex 'marriages' the question has begun to be raised more and more insistently as to whether churches should not offer a blessing to those who have entered into civil same-sex 'marriages' or even conduct same-sex 'marriages' themselves. The Scandinavian Lutheran churches with whom the British and Irish Anglican churches are in communion through the Porvoo agreement have all moved in this direction from 2009 onwards and since 2013 three Anglican churches have begun to move towards the introduction of same-sex 'marriages' with the Anglican Church of Canada being the first to move in 2013 and the Scottish Episcopal Church and The Episcopal Church following them in the summer this year. The Church of England has so far resisted the idea that it should move in the same direction, with the traditional Christian view of marriage being upheld in its 2013 Faith and Order Commission statement Men and Women in Marriage and in the House of Bishops Pastoral Guidance on Same Sex Marriage issued in February 2014. However, since same-sex 'marriages' became legal in Great Britain in 2014 a number of Church of England laity and clergy have entered into them. In addition the majority report of the House of Bishops Working Group on Human Sexuality (the 'Pilling' report) recommended in 2013 that priests should 'be free to mark the formation of a permanent same sex relationship in a public service' and if this recommendation eventually becomes Church of England policy the pressure to move from this half way house to the solemnization of same-sex 'marriages' will become acute. What all this means is that although the debate about the blessing of same-sex relationships and the ordination and consecration of those in such relationships have not gone away the new storm centre in the Anglican Communion is going to be same-sex 'marriage.' In this paper I provide an introduction to this debate by setting out and assessing the arguments for same-sex 'marriage' put forward in reports from the Scottish Episcopal Church, The Episcopal Church and the Anglican Church of Canada. At the end of the paper I will give an overview of what I think we have learned about the key issues in the debate and the challenges facing the Church of England and the Anglican Communion. The full version of this report (including footnotes) can be downloaded here in PDF format.