The Hitchin Society is a founder member of Civic Voice, the national organisation representing civic societies. It is also a member of:
CPRE - Hertfordshire, the county branch of CPRE, defending the Hertfordshire countryside
The Chiltern Society, protecting the Chiltern Hills, stretching to the edge of Hitchin
ANTAS (Association of North Thames Amenity Societies), an association of civic societies throughout Hertfordshire and Buckinghamshire, and beyond.
The British Association for Local History, the national organisation for local history.