Although the Commonwealth Day Observance is project-managed by the Royal Commonwealth Society (RCS), the Council of Commonwealth Societies (CCS) mandates the RCS to deliver Commonwealth Day.
The CCS is a group of organisations connected to the Commonwealth. For a full list of CCS members, click 
here. Its aim is to promote understanding of the people and cultures of the Commonwealth through the celebration of Commonwealth Day. The CCS's objectives are to promote Commonwealth Day in the United Kingdom and internationally and to organise the annual Commonwealth Day Observance held at Westminster Abbey in London.
The Chair of the CCS is Lord Watson of Richmond CBE.