Publications provide the primary means of communicating the results of the NIST programs and services to its varied technical audiences, as well as to the general public. NIST issues some fifteen categories of publications including three periodicals, ten non-periodicals series, interagency reports, and papers in the journals and books of professional organizations, technological associations, and commercial publications. The calibration services, standard reference materials and related measurement services along with changes and fees are published in two Special Publications (SP's) and their supplements. These are SP 250 “Calibration and Related Measurement Services of the National Institute of Standards & Technology” 1 and SP 260 “NIST Standard Reference Materials Catalog.” 1 A complete catalog of all publications by NIST authors is issued annually as a supplement to SP 305 “Publications of the National Institute of Standards & Technology.” Announcements and listings of recent NIST publications and services are published in each issue of the bimonthly “NIST Journal of Research” 2 and the NIST monthly magazine, “Dimensions/NIST” 2. Complete citations to NIST publications, along with information on availability are published bimonthly in the “NIST Publications Newsletter”, available free from the Technical Information and Publications Division, National Institute of Standards & Technology, Washington, DC 20234. NIST publications are also announced (with abstracts) in “Government Reports Announcements and Index” published every two weeks by the National Technical Information Service (NTIS), Springfield, Virginia 22161 3 . NTIS also sells microfiche copies of all NIST GPO-published documents, as well as paper copy and microfiche versions of NIST Interagency Reports.