In the basement of the Cathedral of St. John the Divine, an idea was born by a group of concerned residents, neighborhood activists, community leaders, and service providers. This group of citizens decided to form and organize a not-for-profit corporation whose primary objective would be to tackle "housing and community deterioration". In 1983, the Cathedral Housing Development Corporation was established to revitalize a declining housing community by formulating and implementing plans for the renewal, rehabilitation, and new construction of residential buildings in the surrounding communities. Thus, the organization's name was officially changed to, Ecumenical Community Development Organization (ECDO).

ECDO cut the ribbon and opened the doors to its first inter-generation and special needs housing facility known as ECHO (Ecumenical Community Housing Organization) Apartments in 1991. Ironically, ECHO is located directly across the street from the Cathedral of St. John the Divine. Since then, ECDO has developed affordable housing throughout West Harlem, Manhattanville, Hamilton, and Morningside Heights.

Today, ECDO is a multifaceted organization involved in a variety of community and city-wide activities. ECDO has played an integral part in the formulation of a 197a Plan that was developed by Manhattan Community Board #9. While implementing the organization’s original goal and mission of "combating community deterioration".

ECDO has organized and maintained active participation by holding memberships with numerous consortiums of housing advocacy and community service providers throughout the country. ECDO’s community services include tenant and community organizing, counseling, career training, and job placement assistance to youth and adults along with housing development. The idea of community unity and cooperation remains a prevalent part of each one of our programs, projects, and overall organizational development.