Pyroelectric detectors offer the advantages of room temperature operation and wide spectral response. High performance requires good thermal design of the detector and its mounting structure to maximize low frequency responsivity and to minimize temperature noise. The intrinsic detector noise is caused by dielectric losses. In the crystalline ferroelectrics, such as Sr 0.5 Ba 0.5 Nb2O6 (SBN) and LiTaO3, dielectric loss tangents on the order of 0.0003 have been obtained and a intrinsic detector noise may be limited by material impurities. A low frequency D* of 2 x 109 cm Hz /W has been measured for these materials. At these loss tangent values, temperature noise and preamplifier noise for both JFET and CCD amplifiers presently limit performance. Despite its lower pyroelectric coefficient, the polymer PVF2 is a competitive pyroelectric material for detector arrays using CCD signal processors.