As the world of naval warfare transforms, one book stands out in telling us how that world is changing. Norman Friedman’s compendium, the Naval Institute’s Guide to World Naval Weapon Systems, is much more than statistical data listing weapons, sensors and systems. It tells us about the critical relationships between components to make systems; how systems create networks; and what that means for the navy that employs them. And it does all that in a way that is very readable and understandable.