Recent developments in diamond turning of optics are reviewed. Improved surface figure and surface finish have been achieved as well as metrology of the machined part. Reflectivities of diamond turned metals at various wavelengths are summarized. Application of diamond turned optics include laser resonator mirrors, x-ray microscopes, x-ray telescopes, missile optics, and scanner mirrors. The technology looks especially promising for present infrared requirements since both reflective, refractive, and transmittive components can be fabricated. Diamond turning of optics can be defined as the use of a diamond tool on a precision lathe under very precisely controlled machine and environmental conditions to fabricate a finished optical component. The specific application of precision machining principles to diamond turning has been led by the Lawrence Livermore Laboratory (LLL), Livermore, California and Union Carbide Y-12 Plant (Y-12), Oak Ridge, Tennessee.