The Church of England's General Synod, the church's main legislative body, began meeting in York yesterday and will run through until 13 July 2010.
At least two full days will be devoted to debating and amending an 11-clause measure dealing with the legal requirements for enabling women bishops and outlines provisions for those who will not accept their episcopal leadership, writes Matthew Davies from the Episcopal News Service.
A measure is a piece of legislation that, once passed by the General Synod, requires approval by the UK Parliament.
Of the 40 or more proposed amendments, the ones which have received the most attention are those submitted jointly by the archbishops of Canterbury and York suggesting arrangements whereby two bishops could exercise episcopal functions within the same jurisdiction.
Their proposals call for "co-ordinating" the ministry of a diocesan bishop with another bishop who would provide episcopal oversight for those opposed to female bishops.
A Lambeth Palace press release says the amendments would preserve a female bishop's episcopal authority while providing an alternative for those who are "unable to accept the new situation…"
But the archbishops' proposals have been harshly criticised by supporters of women's ordination and are widely regarded as concessions to traditionalists.
"If the amendments are passed, the church will be in a position of allowing that it is legally acceptable to recognise that women are bishops - and equally acceptable to insist that they are not," said Christina Rees, a lay member of Synod.
"The damaging and undermining effect this would have on women's ministries and on the mission and message of the church overall is incalculable," said Rees, former chair of campaign group Women and the Church, or WATCH.
The archbishops' proposals "seem to have been designed to keep a small minority of people in the church rather than to attract those who are not yet part of the church or to do what is right for the church overall at this time."
General Synod voted in February 2009 to send a draft measure on women bishops to a revision committee so it could rework the legislation.
That draft measure had two principal objectives: "to give the General Synod power to make provision by canon allowing women to be consecrated as bishops; and to set out the legal framework for the arrangements to be made for parishes which, on grounds of theological conviction, feel unable to receive the ministry of women."
The revision committee met 16 times since May 2009 and considered 114 submissions from members of the General Synod, and a further 183 submissions from others. In May 2010, the committee published its 142-page report, which offers a detailed analysis of the draft legislation.
The Church of England opened the priesthood to women in November 1992, five years after women were first ordained to the diaconate.
In the Anglican Communion, formal discussion and debate on women's ordained ministry began in 1920 when the Lambeth Conference called for the revival of the deaconess order, saying that it was "the only order of the ministry which we can recommend that our branch of the Catholic Church should recognise and use."
The first woman priest in the communion, Li Tim-Oi, was ordained in 1944 in Hong Kong. In 1974, there was an "irregular" ordination of 11 women in the US-based Episcopal Church, which officially authorised women's priestly ordination two years later.
Four provinces of the Anglican Communion currently have women serving as bishops - the US-based Episcopal Church, the Anglican Church of Canada, the Anglican Church of Australia, and the Anglican Church in Aotearoa, New Zealand and Polynesia. The Episcopal Church of Cuba also has two female bishops. Eleven additional provinces have approved the ordination of women bishops but have yet to appoint or elect one.
Bishop Barbara Harris, now retired suffragan bishop of Massachusetts, became the Anglican Communion's first woman bishop at her consecration in 1989. The Rev Canon Nerva Cot Aguilera became the first female Anglican bishop in Latin America when she was consecrated bishop suffragan of the Episcopal Church of Cuba in June 2007.
In the Church of England, more than 5,000 women have been ordained as priests since 1994 and today they represent nearly 40 per cent of all clergy.
But Christina Rees lamented that if the legislation passed in General Synod in 1992 "that made it possible for women to be priests had not also explicitly made it illegal for women to be bishops, it is certain that there would have been a number of women serving as bishops in the Church of England for the past decade."
If General Synod passes the current legislation, in whatever form it finally agrees to, it will refer the measure to diocesan synods for consideration. Diocesan synods cannot further amend it. Should a majority of diocesan synods approve the measure, the legislation will return to General Synod for final approval.
Assuming all stages of the legislative process proceed without delay, "it will be at least another two years before the mind of the Church of England can be determined at the final approval stage," the Church of England bishops said in a May statement. Since the measure also would require parliamentary approval, the first woman bishop could not be consecrated until at least 2014.
Parliamentary approval is required because the measure effectively changes English law as the Church of England is an Established church with Queen Elizabeth II as its supreme governor.
Throughout the weekend, prayer vigils for the women bishops legislation are being held at cathedrals in Ripon, Newcastle and Guildford bringing together people from across the spectrum of opinion.