Try this website for a start this discussion. http://foundationforphotographicpreservation.org/
This sort-of started when Ansel offered his work to the University of California. UC replied "Ansel who?", and U of Arizona in Tucson ended up with his work.
About 1982 or 1983 Steve Crouch, author of "Steinbeck Country" and several other regional books passed away and his ex-wife ended up with his archive. she passed on and his son called my mentor and colleague Al Weber and said he was on the way to the dump... Needless to say, the work was rescued and found a home with the now more enlightened U of C. The story repeats many times.
Chuck Guilder in Evert, Wash. found a place with the Nebraska Historical Society for his archive, but it wasn't withou a hitch, they wanted $$ to handle the collection. Chuck's solution was to print a limited edition portfolio to sell to patrons to finance the aquisition.
There are many approaches, but now's the time to start thinking over the process and get things set up properly and there's info available.