If you import a KBART file, then reimport it a few months latter, you may want Koha to treat the file in different way, depending on its origin and of your workflow : - add new titles, and nothing else - add new titles, and update existing titles if they are modified in the KBART (ex : new URL, new dates...) - add new titles, and remove titles if they are no more in the KBART file - add new titles, and update or remove Currently Koha only add new titles, and nothing else (or maybe I did not test it well?), so the other actions could be proposed as options.