Books, audio and video tapes, maps, and posters are available at each national park visitor center or may be purchased by mail.
Numerous titles are available by mail order.
Founded in 1938, SPMA aids and promotes the educational and scientific activities of the National Park Service. As a nonprofit organization authorized by Congress, SPMA makes interpretive material available to park visitors by sale or free distribution. All net proceeds support the interpretive and research programs of the National Park Service.