> I have been asked some questions about the MARC 21 change OCLC implemented
> on Monday.  As explained in OCLC technical bulletin 252, "ISSN (Continuing
> Resources 008/20 & 006/03) will be deleted from Serials records and
> displays. Existing data will be converted to appear in field 022 subfield
> X2. Conversions will take place after the OCLC-MARC Update is implemented
> and deletion of the element will take place after conversions are
> complete."
>
> The background to this change is that when the International Serials Data
> System (now the ISSN Network) was set up in the early 1970's, there were
> few enough ISSN centers that only one character position was needed in the
> MARC format to accommodate the centers (both numerical and alphabetical
> characters were used).  Over the years, as the Network grew, one character
> position was not enough.  For many years, only a limited number of ISSN
> centers were represented in the "ISSN" position in the fixed fields (U.S.,
> Canada, ISSN International Centre, and all others have used "z").  When
> the ISSN Network adopted MARC 21 in place of its own "ISSN MARC" format,
> it proposed to MARBI that a new subfield in field 022 be established to
> contain the ISSN center codes.  This change has just been implemented in
> OCLC.
>
> Regina
>
> Regina 	R. Reynolds                     email: rrey@loc.gov
> Head, National Serials Data Program     voice: (202) 707-6379
> Library of Congress                     fax    (202) 707-6333
> 101 Independence Avenue, S.E.           ISSN Web page: lcweb.loc.gov/issn/
> Washington, D.C. 20540-4160
>