Rules for assignment of ISSN and determining when a new ISSN is necessary
are contained in the _ ISDS Manual_ which is the manual that ISSN centers
throughout the world use in making ISSN assignments and creating ISSN
records.  In the U.S., ISSN are assigned by the National Serials Data
Program at the Library of Congress.  Our phone number is (202) 707-6452
and we are happy to answer questions about title changes that might
require a new ISSN.  We prefer to work with the publisher of the serial
and, in cases where a new ISSN is required but the publisher continues to
print an ISSN of a former title, will contact the publisher and request
that he apply for a new ISSN.

Regina Reynolds
Head, National Serials Data Program
Library of Congress
Washington, D.C. 20540-4160
(202) 707-6379
rrey@loc.gov_