Hello, As we add new libraries to our consortium catalog, I find that we are encountering bib record duplication. Most of this duplication appears to be due to one library using a record that has a 10 digit ISBN, while another library used a record that has a 13 digit ISBN. I am sure that this is a problem many of you have encountered. I would like to pose a couple of questions to the group: First, is it your experience that Koha only matches on the first instance of an ISBN in the 020 field? Does the matching engine follow through and check the second 020 field for a matching ISBN? Second, would the development of a built in ISBN 10 to ISBN 13 converter in Koha matching reduce the number of record duplicates? My inclination is that it would. Thanks for your thoughts on this. Tom Tom McMurdo Collections & Digital Initiatives Librarian Vermont State Library 109 State St. Montpelier, VT 05609-0601 Phone: 802-828-6953 Fax: 802-828-2199 thomas.mcmurdo@state.vt.us