Back in the 1960s, when Yannoulatos first fell ill to malaria, his doctors told him that he would never be able to work overseas as a missionary. The providence of God spoke differently. In 1980, the Orthodox Church of East Africa faced great difficulties. The region had been the most active Orthodox mission field in the world over the past two decades. The church’s footing, however, was jeopardized by internal problems that ultimately led to the defrocking of a Kenyan bishop by the Patriarchate of Alexandria. The East African Orthodox Church seemed to be on the verge of collapse.
   During this time Patriarch Nicholas, the head of the Orthodox Church in Africa, invited Bishop Anastasios to become acting archbishop of the Archdiocese of East Africa. The bishop consented, but continued to keep his responsibilities both at the University of Athens, as well as in Apostoliki Diakonia. During this transitional period, Yannoulatos saw his role as one of re-organizing the church of East Africa. His main priority was to create a strong Orthodox community led by local leaders.
   By focusing on the training and establishing of indigenous leaders, Bishop Anastasios remained faithful to Orthodox missions tradition. As he noted in an earlier writing, “The “incarnation” of God’s Word in the language and customs of a country has been and must be the first concern of all Orthodox mission. Its intent is the planting and growth of a native Church, self-powered and self-governing, able to turn to account all the genuine strands of national tradition, transforming and hallowing them in harmony with the people’s nature, to the glory of God”.
   In 1972, Archbishop Makarios III of Cyprus built an Orthodox seminary in Nairobi, Kenya, but political instability in Cyprus prevented the Archbishop from completing his project. The school remained vacant for ten years. Bishop Anastasios’s first action as the new leader of the church was to finish the seminary and open it immediately. During the 1970s, many of the faithful within the African Orthodox Church became disillusioned and disheartened with the floundering church, and began to leave. Yannoulatos realized that the only way to bring these people back, as well as to bring new converts into the faith, was through the training of local leaders and priests.
   Hence, Bishop Anastasios officially opened the “Archbishop Makarios III Orthodox Patriarchal Seminary” in 1982. Over the following decade, the school averaged forty-five students annually, using twelve professors from East Africa, Europe, and the United States. The acting archbishop eventually ordained sixty-two priests and deacons, as well as forty-two readers and catechists from the school’s graduates These indigenous leaders came from eight different tribes in Kenya, Uganda, and Tanzania, and provided the foundation for the renewal of the church in East Africa.
   Along with training local leaders, the acting archbishop also supported the Orthodox  missionary tradition of translation, which he believed was sanctioned by Christ during the event of Pentecost. Thus, he concentrated on publications, organizing the translation of services into seven different languages. Bishop Anastasios also tried to establish a sense of permanency in the structures of the church by guiding the construction of sixty-seven new church buildings, twenty-three of them stone and forty-four wooden and mud. He also helped renovate twenty-five existing church buildings. His construction accomplishments included seven mission stations, seven health  stations, five primary schools and twelve nursery schools.
   His work in Africa drew worldwide attention. The Greek Orthodox Church in America  assisted him by sending missionaries to East Africa. The impact of these missionaries was felt not only within the church of East Africa, but also throughout America. Many of the short-term missionaries returned to their homes in the United States, and helped increase a missionary awareness and consciousness within their own parishes. The Orthodox church in Greece and in Finland also responded to a series of lectures the bishop gave on the imperative of missions by  sending missionary teams of their own to Kenya.
   The most important aspect of Bishop Anastasios’s work in East Africa, however, was not the ordinations, the publications, or the missionary interest created by the mission teams. It was instead his efforts to assimilate with the indigenous Christians. By identifying closely with the Orthodox Christians of this region, he encouraged and empowered them to embrace the faith as authentically their own. As a result, the church of East Africa continued to mature even after his departure as acting archbishop in 1991.
   In addition to his achievements in Africa, Bishop Anastasios has left his mark in other ways. In 1981, the Bishop began editing, through the auspices of Apostoliki Diakonia, the first official missionary magazine of the church of Greece, entitled Panta ta Ethne (All Nations). This magazine continues to disseminate mission information, and challenge Orthodox Christians throughout Greece to respond to the missionary mandate.
   The 1980s also saw Bishop Anastasios intensify his activity in the WCC. After participating in the World Mission Conference at Melbourne in 1980, as well as the general assembly of the WCC at Vancouver in 1983, the Bishop became the moderator of the CWME during 1984-91, and presided at the World Mission Conference at San Antonio in 1989. His missiological impact not only influenced the Orthodox world, but also touched broad ecumenical circles. As the prominent Protestant theologian and missionary David J. Bosch noted,
   “Anastasios has remained the driving force behind the missionary movement in Orthodoxy. And since the Orthodox churches joined the WCC in 1961, he and others have made a major contribution to missionary thinking and practice in ecumenical circles… The cross-fertilization in the area of Missiology between Orthodoxy and Protestantism has indeed been a major area of theological renewal in the ecumenical movement since 1961. Only three papers were read in the conference plenary during the first few days… Whereas the first two papers were interesting and challenging, it was Anastasios’ presentation that provided the theological framework for the conference theme “Your Will Be Done”… its overall thrust was truly ecumenical in the best sense  of the word.”