California Preservation Foundation
http://www.californiapreservation.org/
DOCOMOMO, International
http://www.docomomo.com/
DOCOMOMO, U.S.
http://www.docomomo-us.org/
DOCOMOMO, U. S., Northern California Chapter
http://www.docomomo-us.org/chapters_northern_california.shtml
Los Angeles Conservancy
http://www.laconservancy.org/index.shtml
Modern Committee of the Los Angeles Conservancy
http://modcom.org/
National Trust for Historic Preservation
http://www.nationaltrust.org/
Pasadena Heritage
http://www.pasadenaheritage.org/
San Diego Save Our Heritage Organisation
http://www.sohosandiego.org/
Santa Barbara Trust for Historic Preservation
http://www.sbthp.org/presidio.htm
California Office of Historic Preservation
http://ohp.parks.ca.gov/
National Parks Service, Cultural Resources, site map
http://www.cr.nps.gov/sindex.htm
California Parks Association
http://www.calparksleague.org/contact.html