The American Association of Museums, the “AAM is aware of only two attempts to count all the museums in the United States. The most recent effort estimates 17,500 museums.
One of the attempts to count museums was a survey conducted for the National Conference of State Museum Associations in 1998. The survey counted 15,848 museums. This number, however, was extremely approximate. Some state museum associations reported the number of museum members of their association; other states provided an estimate of the total number of museums in their state.
The second effort was the database of museums compiled by the Institute of Museum & Library Services (IMLS). The database combined the IMLS database of museums that have participated in IMLS programs, the print version of The Official Museum Directory (2000), and the Museums USA database provided by the State Museums Association. IMLS used a variety of techniques to eliminate duplicates and confirm listings. The database contained 18,410 organizations in 2005. IMLS thinks that approximately 5% of the entries are for non-museum organizations, leaving an estimated total of 17,500 museums.”
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