PDA

I was posting yesterday about public libraries, and I've been reading about the Patron Driven Acquisitions (PDA) model. Apparently this model is kind of a huge and headachey success, and so it's sort of a problem to figure out how exactly libraries want to proceed with it. It's expensive on the one hand, and also so wildly successful that it sort of defies any attempts to get rid of it once it's in place.
For the project I'm working on, we're talking about building libraries in third world countries, in places where there is not a book culture already present. Or at least not for many people. In this kind of scenario, I think that the PDA model will actually work very nicely. You don't have thousands of undergrads, or even hundreds of public library patrons, banging down the door for their chance to print out their own books. I imagine that the acquisitions would happen more slowly, as people get used to the idea that it's even possible to have on-demand books streaming to you on the web.
I'm not an acquisitions librarian, nor a reference librarian, and so I'm not really very knowledgeable about this aspect of libraries. Catalogers usually just take what we're given, and we make it available and hope for the best. This is definitely a new adventure.