The rulebook a fair publishes before its run, in print or as a download, listing every competitive class, entry deadline, eligibility rule and cash premium on offer. If you intend to enter anything, from a market heifer to a jar of pickles, the premium book is the document that governs it. Entry deadlines commonly fall weeks before the fair opens, so finding it early matters more than the fair's own date range does.
Also known as: premium list, exhibitor book.