I bought this before I attended the RYA 1 & 2 powerboat courses. This RYA book covers all the theoretical information that you need for the ICC qualification (RYA1 & 2). The illustrations are clear and easy to understand and help to clarify specific points in the theory. The book is useful as an introduction to boating and also a a reference book. I have been boating for several years and this book taught me a great deal - the things that all skippers should know. I would highly recommend this book for beginners and also as a reference book.