Unitas Ecclesiarum represents an original work onan ecumenical topic of great interest between theChurches of the East and West. In exploring thedistintion between method and model, the authoroffers some new perspectives on the centuries oldissue of sui generis churches. Through a constantre-reading of the fundamental texts of the SecondVatican Council as wella as other conciliar textsand magisterial documents, Mr. Dzyubanskyy ar-rives at establishing a heuristic model for aiding theunderstanding of the issues at stake in dealing withthe question of Uniate churche.