Nuclear and space radiation can produce a number of undesirable effects in infrared detectors. Steady-state ionizing particle fluxes, such as electron, proton, or gamma fluxes, produce a series of pulses in both intrinsic and extrinsic detectors. Many of these pulses have amplitudes large enough to result in their detection as false signals by the sensor. Alternatively, the combined effect of such pulses is to increase the rms noise level and the leakage current in the detector. Steady-state ionizing fluxes also cause an increase or a decrease in the optical response in extrinsic silicon detectors as a result of the trapping of the ionization-generated carriers on the optically active sites. Displacement damage, caused by electron, proton, or neutron fluences, gives rise to centers that decrease the optical responsivity. In extrinsic detectors, this decrease is the result of the radiation-induced defects compensating the optically active sites. Total-dose deposition has its largest effect in insulators and at semiconductor-insulator interfaces. This is particularly trouble-some in detector arrays where interaction between previously isolated elements can result. Total-dose deposi-tion can also affect the characteristics (decreased zero-bias resistance and increased reverse leakage current) of photovoltaic detectors. The purpose of this paper is to present an overview of the effects that radiation can produce in infrared detectors.