ffects has been characterized and hardening solutions have been successfully implemented in many cases. The most commonly used CCD for visible and UV detection is the buried channel device which has a shallow n-type layer implanted below the surface to keep the stored signal charge away from the traps associated with the Si/SiO2 interface. Such CCDs may be hardened to TID effects either by the use of radiation hardened oxides [Carb93], or by biasing the device SO that the silicon surface is inverted SO that the interface traps are filled and dark current generation is suppressed [Saks80]. This can be achieved with an extra implantation to form a multiphase pinned device [Jane95], or by shuffling the charge back and forth between gates within a pixel faster than the surface states can respond (so-called dither clocking) [Burk91, Hopk92] Bulk displacement damage effects often dominate the radiation response in state- of-the-art scientific imagers when operated in natural particle environments IV-79 [e.g., Jane91, Holl91b]. The flatband shifts and dark current increases that occur for ionizing dose levels below 10-20 krads(Si) are often not serious, and can be overcome with minor changes in voltages and operating temperature. In contrast, significant CTE losses are observed for proton exposures of less than 1 krad(Si). Nevertheless, the degree of CTE loss that is tolerable is very application-dependent, and it is still possible for a device to ultimately fail as a result of either TID or displacement damage effects at higher exposure levels. It is important to verify that flatband shifts will not take a device out of inversion prior to the expected mission dose, and also to ensure that the readout amplifier circuitry is robust. A detailed description of proton effects in CCDs may be found in a recent review article [Hopk96] and references therein. Displacement damage degrades CCD performance by decreasing the CTE, increasing the average dark current, by introducing individual pixels with very high dark currents (or 