In 1990 he was named Coadjutor Archbishop of Dar es Salaam, and in 1992 he became Archbishop of Dar-es-Salaam, following the resignation of Cardinal Laurean Rugambwa.
Godine 1990. bio je imenovan koadjutorom nadbiskupije u Dar-es-Salaamu, a 1992. postao je nadbiskupom Dar-es-Salaama nakon ostavke kardinala Laureana Rugambwa.