It is certainly eagerness of every manufacturer to be able to look through a finished product without destroying it. Indeed, using modern technology within the application of some physical principles makes it possible to really travel inside the matter and see the invisible. Nondestructive inspection, non destructive testing and non destructive evaluation are today recurrent terms in many fields from the high-tech development to the past footsteps conservation. This book collects theories and practices for several different non-destructive inspection techniques, which is certainly a great advantage since it facilitates the user's choice, while it may be breeding ground for generating and promoting new ideas for a better exploitation of a specific technique.