A www.software.coop associate is willing to extend Koha so that book-and-CD sets can have security tags on each unit.

I think what we're looking at here is a sort of “requiring item” (sorry but I can't find the correct term for this) where unit 2 (the CD in this example) may only be issued if its requirements are met - that unit 1 is already issued to the borrower, and similarly on return.

I would need to add an item field and linked MARC subfield to Koha so a cataloguer can set this as a reason not to issue an item but I don't see any particular problem with that. Would that seem a sensible approach to you?

Edit From HDL

Very Nice feature.

But Is this the way to implement that ? should it not be managed via a kind of holding level ? a “virtual” holding would be linked to all the holdings in the subset. And we would check the father only when all children are checked out.

We need the same kind of father/son relations for Biblios, and we have kind ot that for authorities. This would allow to have the list of all the holdings of the subset on screen at once when trying to check out a single item of that set. Just my 2 cts.

Response from MJR

This has been delayed by non-enhancement matters. It needs a wider discussion of parent-child biblio relations which I have not initiated.

May relate to Implementing summary records