Silicate garnet is a key rock-forming mineral, and various synthetic nonsilicate garnets find important use in a number of technological areas. Garnet's crystal structure provides the basis upon which many microscopic–macroscopic property relationships may be understood. Most rock-forming garnets are substitutional solid solutions and, thus, mineral scientists are focusing their efforts on investigating local structural properties, lattice strain, and thermodynamic mixing properties. Nonsilicate compositions are used, or have potential use, in various scientific and industrial areas because of their magnetic, optical, lasing, and ion-conducting properties. Research on garnet is multidisciplinary and involves scientists in the materials and mineral sciences, physical and inorganic chemistry, and solid-state physics.