Recent progress in developing new methods for the epoxidation of unsaturated compounds has been reviewed. Newly developed epoxidizing reagents as well as modified methods utilizing conventional epoxidizing reagents are described. These include epoxidations with (1) peracids, (2) activated hydrogen peroxide, (3) molecular oxygen, and (4) miscellaneous reagents. Particularly, stereocon-trolled epoxidations and asymmetric synthesis of epoxides are emphasized.