American Institute for Conservation
http://www.conservation-us.org/

The American Institute for Conservation of Historic & Artistic Works (AIC) is the national membership organization supporting conservation professionals in preserving cultural heritage by establishing and upholding professional standards, promoting research and publications, providing educational opportunities, and fostering the exchange of knowledge among conservators, allied professionals, and the public.

Find a conservator - http://www.conservation-us.org/membership/find-a-conservator

Northeast Documentation Conservation Center
https://www.nedcc.org/

NEDCC is the first independent conservation laboratory in the nation to specialize exclusively in treating collections made of paper or parchment, such as works of art, photographs, books, maps, manuscripts, and more. The Center offers conservation treatment, digital imaging, and audio preservation services, as well as training, consultations, and  disaster advice for collections.

Conservation Center for Art and Historic Artifacts
http://www.ccaha.org/

CCAHA specializes in the treatment of works of art and artifacts on paper, such as drawings, prints, maps, posters, historic wallpaper, photographs, rare books, scrapbooks, and manuscripts, as well as related materials such as parchment and papyrus. CCAHA also offers on-site consultation services, educational programs and seminars, internships, and emergency conservation services.

Library of Congress Preservation
http://www.loc.gov/preservation/