Gonioscopy is a very important differential diagnostic tool that permits assessment of the anterior chamber angle and correct classification of glaucoma as a basis for specific treatment. This book clearly explains how to perform gonioscopy to best effect. The anatomy of the chamber angle is systematically described, and the impact of age, developmental disorders, and other pathologies on the chamber angle is explained. Particular attention is focused on primary and secondary open-angle and angle-closure glaucomas. In each case, the role of gonioscopy in evaluating the chamber angle is described with the help of many photographs and illustrations. The importance of knowledge of the chamber angle for