The ninth series holds information about the numerous organizations the National Association of the Deaf was involved with. Since the NAD is the primary representative body for the United States with the World Federation of the Deaf, cooperation with national organizations was important to best serve the deaf in the US. Similarly, the NAD was active in the exchanging of information and ideas internationally; therefore, information about organizations from around the world is also located in this series. Also present are documents relating to the different committees of the NAD.