Hi, All -- Koha's Batch Record Modification (BRM) tool makes it very easy to make large-scale changes to the catalog. And we know that many catalogers like to have their records just so :-) Is there a cost in overhead, however, to making such changes? For example, if a catalog of 150,000 records contains 75,000 unwanted MARC fields, would you delete them, even if they're not displayed in the OPAC or otherwise interfering w/ functionality? In particular, I'm wondering whether using the BRM tool involves the creation of new data so that there's no real net gain w/ respect to the goal of having a "cleaner" database. (In our case, we've turned off the CataloguingLog system preference.) Along the same lines, are there any advantages to doing large-scale batch process via the backend instead, i.e., as opposed to w/ the built-in staff tools such as BRM? (I'm assuming there's no issue w/ using such tools to work w/ much smaller subsets of records.) Thanks in advance for any guidance. All best, Cab Vinton, Director Plaistow Public Library Plaistow, NH