If you are looking for a book that tells you what aperture and shutter speed to use for every possible situation, go buy something else. BUT if you are looking for a small book that you can easily stow in your bag and is packed full of useful advice from some of the world's greatest photographers then this is probably the only book you will need. The book concentrates on what you are trying to convey in your photos, tips on composition and how to effectively use light. In addition to the text there are several one page tips from top National Geographic photographers. There are short non-technical chapters on cameras and lenses and digital processing. Well worth the money.