This second volume of the series Lectures in Optics develops a thorough presentation of geometrical optics effects. The book begins by discussing refraction and reflection off single surfaces, both flat and spherical. Presented next are the essential building elements, optical power and beam vergence, which are paramount in imaging because the incident vergence is added to the element’s power to produce the vergence leaving the optical element. Imaging definitions and formulation are covered next, followed by the power configurations and imaging arrangements possible with a single element, a single lens, and a mirror for real and virtual objects. Next, two more parameters are introduced: the extent of an element along the optical axis (thick lenses and lens systems) and the extent of an element perpendicular to the optical axis (stops and pupils). The way image quality is affected by the transverse restriction of light is then discussed, including resolution and image blur. Finally, the book introduces the concepts of optical aberrations as a consequence of a violation of the paraxial approximations. This book is suitable for all Geometrical Optics courses at college, graduate school, or professional school levels, such as physics, engineering, visual science, or optometry programs. Comprehensive practice examples, exercises, and quizzes throughout the chapters reinforce an understanding of the covered material.