The OAS is a nonprofit, voluntary, scientific and professional society incorporated in the District of Columbia. The membership of OAS consists of state radiation control directors and staff from the 37 Agreement States who are responsible for implementation of their respective Agreement State programs. The purpose of the OAS is to provide a mechanism for these Agreement States to work with each other and with the United States Nuclear Regulatory Commission (NRC) on regulatory issues associated with their respective agreements.

Agreement States are those states in the United States of America that have entered into an effective regulatory discontinuance agreement with the NRC under subsection 274b. of the Atomic Energy Act (AEA). The role of the Agreement States is to regulate most types of radioactive material in accordance with the compatibility requirements of the AEA. These types of radioactive materials include source material (uranium and thorium), reactor fission byproducts, and quantities of special nuclear materials (SNM) not sufficient to form a critical mass. Under its own internal practices, the NRC periodically reviews the performance of each Agreement State to assure compatibility with NRC's regulatory standards.

Agreement States issue radioactive material licenses, promulgate regulations, and enforce those regulations under the authority of each individual state's laws. The Agreement States exercise their licensing and enforcement actions under direction of the governors in a manner that is compatible with the licensing and enforcement programs of the NRC.