Injection molding of optical components on a production basis began in 1980. Development took place from the mid to late seventies with the potentially high volume defense contracts candidates for injection molding. Plastic optics are lower cost and lighter weight than optical glass. Also, injection molding offers the capability to produce complex shapes which are functionally integrated with other metal and/or plastic components. Lenses and domes with aspheric or spheric surfaces and internal or external threads have been successfully injection molded. These parts would have required costly manufacturing methods or even been impossible to produce. Although initial tooling cost and process development may be high, parts can be consistently produced in large quantities economically. Consistency from run to run is maintained by rigorous process control to ensure the high standards required in optical parts. Polycarbonate is the plastic material used most often to injection mold optical hardware. It is a thermopolastic consisting of linear polymer chains like an acrylic or a styrene but has higher lipact strength and temperature resistance. Polysulfone is also used and has even higher temperature resistance and strength although impact strength is lower. Mold design, process parameters, and part inspection (dimensional, visual, optical) as they relate to the plastic optical components injection molded at Martin Marietta are discussed. Also presented are problems encountered during pre-production and production and the corrective measures, e.g., cosmetic appearance, dimensional control, molded part handling, and enhancement of optical characteristics.