Diamond Materials and Applications presents a broad and contemporary view of diamond as both an advanced engineering material and an emerging functional platform. Renowned for its exceptional hardness, wear resistance, thermal performance, chemical stability, and distinctive electronic, optical, and quantum properties, diamond continues to expand far beyond its traditional roles in cutting, grinding, and drilling. This volume explores the materials science, processing, interfaces, performance, and applications that underpin modern diamond technologies, spanning superhard polycrystalline diamond, drilling materials, extreme-environment electronics, quantum-related diamond, diamond–metal interactions, and precision manufacturing. The book emphasizes the relationships among synthesis, microstructure, defects, interfaces, and application performance, bridging fundamental understanding and practical engineering. By bringing together established industrial uses and rapidly developing technological directions, the book highlights both diamond's maturity as a critical engineering material and its continued evolution into new areas of electronics, sensing, quantum technology, and advanced manufacturing. Diamond Materials and Applications will be a valuable reference for researchers, engineers, graduate students, and professionals working in diamond science, superhard materials, semiconductor materials, drilling technology, precision manufacturing, and related advanced technologies.