Unity-and-Diversity World Council (UDC) is a cooperating body of individuals, groups, and networks, dedicated to cultivating a culture of peace with justice, and to building a sustainable future based on universal ethical and spiritual principles.

UDC is a non-profit, tax-exempt California corporation. It was formed during the United Nations International Cooperation Year in 1965 by Leland Stewart and his wife, Elizabeth.

Since that time, UDC has developed intergroup and interfaith activities on a local-to-basis that are focusing on inner and outer peace, plus looking toward the creation of a people’s equivalent of the United Nations (The Global People’s Assembly). UDC sponsors ongoing events, educational forums, and festivals, as well as publications and multimedia productions.