VOYA: In a standout example of middle grade nonfiction, this cleverly designed, engaging book will answer every question about codes and ciphers?and then some. Well-organized information, presented in chronological sequence (with fifteen chapters ranging from "Clay, Wax, and Greece [1500 BCE-100 BCE]" to "Colossus, Lucifer, and Kryptos [1945 CE-]") is enhanced with a glossary, a brief "Selected Sources" list, a page devoted to related information (including fiction, nonfiction, and online resources), and a comprehensive index. Most pages include a photograph, image, sidebar, or example code. Quotes are referenced in a separate list in the back of the book?not cited in text?which might discourage some readers from exploring primary sources, but the fact that the information is included adds to the integrity of the book. Although the text is presented with engaging, accessible language and lends itself to being read in its entirety, each chapter can be read independently, which will allow the reader with a specific interest to quickly locate and use the information needed. A nicely crafted balance of information about individual people, world events, and technology ensures that the text never feels heavy. Enough background information is offered to orient young readers to the topics discussed, but the author's focus on codes and ciphers is what makes this book so strong. With a topic, style, and format sure to engage middle grade readers, this book will be a great fit for almost any school or public library collection. Reviewer: Ellworth Rockefeller