COMMON If you do something by the book, you do it strictly according to the rules. Modern man is often dull, studious, careful, safe. He does everything by the book. Note: You can also say that you go by the book or play something by the book. They could have taken a stranglehold on the game, but they seemed determined to go by the book and not rush things. The manager of the shop played things by the book, so I was taken down to the police station and charged with theft. Note: You can use by-the-book before a noun to describe a person or their way of doing things. He was content to follow a by-the-book approach. Note: If something is done according to the rules and in the usual way, you can say that it goes by the book. As it looks now, this campaign will not go by the book. It'll be nothing like we've ever seen before.