Concentrating on the design and mounting of significantly larger optics and their structures, this volume details how to design and fabricate very large single-substrate, segmented, and lightweight mirrors; describes mountings for large mirrors with their optical axes in vertical, horizontal, and variable orientations; indicates how metal and composite mirrors differ from ones made of glass; explains key design aspects of optical instrument structural design; and explores the evolution and applications of silicon and silicon carbide in mirrors and other types of components for optical applications.