Some dog training books contain valid information. Others may have techniques not grounded in scientific data or harmful to both owner and pet. A good dog training book presents scientifically based reliable information. The book will structure this information in a format that is easy to read and apply.
As with everything else, there are good and bad choices. Scrutinise the training book to determine whether the principles are sound or counterintuitive. Many great options offer tested and proven solutions with you and your dog in mind. You also have a part to play and must put the techniques into practice. Consistency, positive reinforcement and patience are integral for dog training, regardless of the book you choose.