expertise. Karl Rahner, Joseph Ratzinger and Hans Küng first went to the council as some bishop's personal theologian, and were later appointed official periti. Some notable theologians, such as Edward Schillebeeckx, remained private periti for the whole duration of the council. Observers (§18) . An important innovation was the invitation by Pope John to Orthodox and Protestant Churches to send observers to the council. Eventually 21 denominations or bodies such as the World Council of Churches were represented. The observers were entitled to sit in on all general assemblies (but not the commissions) and they mingled with the Council Fathers during the breaks and let them know their reactions to speeches or to schemas. Their presence helped to break down centuries of mistrust. Lay auditors. While not provided for in the Official Regulations, a small number of lay people were invited to attend as “auditors” beginning with the Second Session. While not allowed to take part in debate, a few of them were asked to address the council about their concerns as lay people. The first auditors were all male, but beginning with the third session, a number of women were also appointed. Main players In the very first weeks of the Council proceedings, it became clear to the participants that there were two “tendencies” among the Council Fathers, those who were supporters of aggiornamento and renewal, and those who were not. The two tendencies had already appeared in the deliberations of the Central Preparatory Commission before the opening of the council. In addition to popes John XXIII and Paul VI, these were the prominent actors at the council: Prominent Conservative Bishops at the Council Cardinal Alfredo Ottaviani: secretary of the Holy Office Cardinal Michael Browne : professor at the Angelicum and consultor for the Holy Office. Cardinal Giuseppe Siri: archbishop of Genoa, president of the Italian Bishops' Conference. Cardinal Ernesto Ruffini: archbishop of Palermo. Archbishop Marcel Lefebvre : superior-general of the Congregation of the Holy Spirit; at the council, he acted as the president of the Coetus Internationalis Patrum (“International Group of Fathers”), the bloc of conservative Council Fathers Prominent Reform-minded Bishops at the Council Cardinal Augustin Bea : president of the Secretariat for Promoting Christian Unity Patriarch Maximos IV Sayegh: patriarch of the Melkite Greek Catholic Church Cardinal Achille Liénart: bishop of Lille (France), the senior French bishop Cardinal Josef Frings: archbishop of Cologne (Germany), the senior German