The juridical aspect of ecumenism is very important. A sign of reception of ecumenical ecclesiology is its integration with canon law. This essay evaluates the value of the Codex Canonum Ecclesiarum Orientalium as an instrument in their hands of the Eastern Churches in communion with Rome for promoting unity between Orthodox and Catholics. It contrasts it with the ecclesiology of the Orthodox-Catholic dialogue on unity. It also shows that in many important points the ecumenical value of this code of law is limiting more than facilitating and reflects the need to integrate the results of the ecumenical dialogue with canonical legislation.