The Mason Valley IOOF Building is significant on several counts. It figured prominently in the development of the City of Yerington, it is a type of building that is rarely found intact in Nevada, and it was designed by noted Nevada architect Frederick J. DeLonchamps.

The Independent Order of Odd Fellows (I.O.O.F.) is an altruistic fraternal organization derived from the similar English Oddfellows service organizations which came into being during the 1700s....Although in Britain the Odd Fellows tended to meet in pubs, in the U.S. the lodges often built their own facilities. Many of these are now on the U.S. National Register of Historic Places....

From Wikipedia entry for Independent Order of Odd Fellows