Updated January 2019. This book is a complete guide to the design, installation, testing and operation of fiber optic networks. It was written with the assistance of many experienced Fiber Optic Association (FOA) instructors in fiber optics as a reference book for classes aimed at FOA CFOT certification as well as a basic reference for anyone working in the field of fiber optics. This book offers expansive coverage on the components and processes of fiber optics as used in all applications and installation practices. A complete curriculum for teaching fiber optics using this book as a text is available from FOA.