Why do we weed the collection? First, we don’t have much choice. We’re running out of space and building a wing onto the library to make room for more books just isn’t in the cards.It would be an irresponsible use of funds. But there’s a more positive reason to weed the collection. Not all books age gracefully. Some weren’t much good to begin with, and they haven’t improved with age. Lots of them confidently state truths that are no longer true, if they ever were. Most of the books we remove are benignly bad – like advice books for executives on how to use computers to improve payroll management circa 1975; they aren’t dangerous unless large numbers of them fall on your head. But others are recklessly bad, such as state-of-the art reviews of how to treat mental illness or how to deal with juvenile delinquency published in 1970. I’m not talking about classics, about books that shaped our thinking and continue to be cited. I’m talking about books that weren’t all that great when they were published. And libraries are full of them.