I’ve been known to lend a book to someone and then forget who I lent it to. And it’s conceivable that the borrower might forget who the owner is. This is one reason that bookplates are a good idea. You can buy them in stores and write your name on them, but personalized, preprinted bookplates are even better. If that’s what you want, go to Bookplate Ink, where you can choose from dozens of black-and-white or color designs. The bookplates are self-adhesive with a peel-off backing and are acid-free.