In addition to the 166 synod members elected by their national bishops' conferences, 22 heads of Eastern Catholic churches, 25 heads of Vatican congregations and councils and 10 heads of men's religious orders, the pope appointed an additional 45 synod fathers to take part in the Oct. 4-25 gathering.

The complete list of synod participants and papal appointees was released Sept. 15 by the Vatican.

The ordinary synod will include many more people than last year's extraordinary synod, which met over the course of 15 days. The ordinary synod will bring together nine additional leaders of Eastern Catholic churches and six more "fraternal delegates" from the Orthodox, Anglican and Protestant communities. The pope also named 45 voting members of the synod -- up from 26 last year -- and he appointed 51 observers and 23 experts, including a total of 18 married couples. At the extraordinary synod, there were 38 observers and 16 experts, which included a total of 14 couples.

Almost half of the 45 papally appointed voting members are from Europe with another 15 from the Americas, three from Africa, two from Oceania and one from Asia. At the extraordinary synod, almost all appointees were from Europe, and none of the papal appointees was from North America or other English-speaking countries.

Pope Francis ensured that all the members of the synod's general council would be present at the October meeting by appointing U.S. Cardinals Donald W. Wuerl of Washington and Timothy M. Dolan of New York as voting members.

In addition, he named U.S. Archbishop Blase J. Cupich of Chicago; U.S. Bishop George V. Murry of Youngstown, Ohio; Canadian Cardinal Gerald C. Lacroix of Quebec; and New Zealand Cardinal John A. Dew of Wellington as members.

Some of the other papal appointees include German Cardinal Walter Kasper, Belgian Cardinal Godfried Danneels of Mechelen-Brussels, and Honduran Cardinal Oscar Rodriguez Maradiaga of Tegucigalpa, as well as Jesuit Father Antonio Spadaro, director of La Civilta Cattolica journal, and Msgr. Pio Pinto, dean of the Roman Rota, a Vatican-based tribunal that deals mainly with marriage cases.

Among 51 observers and 23 experts appointed by the pope, the majority are laymen and laywomen, including 18 married couples. The 42 men and 32 women, who will not have voting rights, represent a more geographically diverse mix with fairly equal representation for Asia, Africa, the Americas and the Middle East, and a slightly higher number from Europe.

The synod's voting members include officials from the Roman Curia, heads of the Eastern churches, and archbishops of smaller Eastern Catholic churches, including Byzantine Archbishop William C. Skurla of Pittsburgh.

Canadian Cardinal Marc Ouellet, prefect of the Congregation for Bishops, and Australian Cardinal George Pell, prefect of the Vatican Secretariat for the Economy, were to attend as officials of the Roman Curia.

Pope Francis will serve as president of the synod and will be assisted by Cardinals Andre Vingt-Trois of Paris; Luis Antonio Tagle of Manila; Raymundo Damasceno Assis of Aparecida, Brazil; and Wilfrid F. Napier of Durban, South Africa.

As he did at last year's extraordinary synod, Hungarian Cardinal Peter Erdo of Esztergom-Budapest will serve as relator with the duty of introducing the discussion and synthesizing its results, and Italian Archbishop Bruno Forte of Chieti-Vasto will serve again as special secretary.

Among those elected to attend by their country's bishops' conferences:

-- Canadian Cardinal Thomas C. Collins of Toronto; Archbishop Paul-Andre Durocher of Gatineau, Quebec, conference president; Archbishop Richard W. Smith of Edmonton, Alberta; and Bishop Noel Simard of Valleyfield, Quebec.

-- U.S. Cardinal Daniel N. DiNardo of Galveston-Houston; Archbishop Joseph E. Kurtz of Louisville, Kentucky, conference president; Archbishop Charles J. Chaput of Philadelphia, host of the World Meeting of Families in September; and Archbishop Jose H. Gomez of Los Angeles.

-- English Cardinal Vincent Nichols of Westminster and Bishop Peter Doyle of Northampton.

-- Scottish Archbishop Philip Tartaglia of Glasgow.

-- Irish Archbishop Diarmuid Martin of Dublin and Archbishop Eamon Martin of Armagh, Northern Ireland, president of the Irish bishops' conference.

-- Australian Bishop Daniel Hurley of Darwin and Archbishop Mark Coleridge of Brisbane; and Bishop Charles Drennan of Palmerston North, New Zealand.

Many of the papally appointed observers and experts are active in family ministries and pastoral care, canon law and moral theology, and did not attend last year's extraordinary synod.

Among the nonvoting members invited to attend are:

-- U.S. Sister Maureen Kelleher, a member of the Sisters of the Sacred Heart of Mary and an attorney who provides legal assistance and attention to immigrants in Florida.

-- U.S. couple Catherine Witczak and Anthony Witczak of Philadelphia, former leaders of the International Ecclesial Team of Worldwide Marriage Encounter.

-- John Grabowski, professor of moral theology at The Catholic University of America, Washington.

-- Moira McQueen, director of the Canadian Catholic Bioethics Institute at the University of Toronto, moral theologian and lawyer who specialized in family law and juvenile court.

-- Pia Matthews, professor of health care ethics at St. Mary's University in London.

-- Maria Harries, research fellow in social work and policy at the University of Western Australia, expert on mental health, child protection, child migrants and social services, and member of the "Truth, Justice, Healing Council" assisting the Australian bishops' response to abuse.

-- John Kleinsman, director of the Nathaniel Centre, the New Zealand Catholic Bioethics Centre.

-- Nathalie and Christian Mignonat, national coordinators of "Les Equipes Reliance" in France and co-founding members of SEDIRE; both associations work with accompanying divorced and remarried Catholics.

-- A Chaldean Catholic couple from Baghdad, Suhaila Salim Toma and Wisam Marqus Odeesho.

-- A Hindu-Christian couple from Mumbai, India, Penny and Ishwar Bajaj.

-- Father Garas Boulos Garas Bishay, a parish priest in Sharm el Sheikh, Egypt, and Maria Gomes, director of the family and life program at St. Mary's parish in Dubai, which helps tens of thousands of foreign Catholics there.

Fourteen "fraternal delegates" will represent other Christian communities, such as the Lutheran, Anglican and Baptist communities. Russian Orthodox Metropolitan Hilarion of Volokolamsk, director of foreign relations for the Moscow Patriarchate, also is expected to attend.

The ordinary general assembly of the Synod of Bishops is focusing on "The Vocation and Mission of the Family in the Church and the Contemporary World." It will draw up pastoral guidelines responding to previous discussions looking at the challenges facing today's families. It is expected the pope will then write a postsynodal apostolic exhortation that takes up the themes of the synod and develops them further.