The organization of the book is as follows. Block diagrams of entire fiber optic systems are presented at the outset. This identifies the components of fiber systems, providing motivation for their individual study in succeeding chapters. Chapters 2 and 3 contain a review of important results from the fields of optics and wave travel. This basic information is needed for an understanding of fiber optic devices and systems. Chapter 4, on integrated optics, introduces the technology of combining optic compo- nents onto a single substrate. The integrated optic waveguide provides an excellent, simplified model for propagation of light in a fiber. Chapters 5-9 present the main de- vices encountered in a fiber optic system. These are the fiber, the light source, the light detector, the couplers, and the distribution networks. System considerations appear in Chapters 10-12, where modulation formats, the effects of noise on message quality, and system design are covered. The last chapter includes examples of operational systems. In that chapter, the design information developed throughout the book is applied to realistic problems.