Guyed structures are commonly used to support electric transmission lines. They generally have the advantage of lightweight, erection ease, pre-assembly, and simple foundation design. There is a considerable range of applications, from simple guyed wood poles to the very large guyed steel latticed structures. This publication describes the various types of guyed structures that have been used; presents typical guys and fittings; illustrates guy anchors and foundations; explores analysis and design techniques specific to guyed structures; discusses unique construction and maintenance problems; and displays both hand and computer calculations to illustrate some of the concepts discussed in the document.