Pyroelectric devices are now widely used in the detection of infrared (IR) radiation in the two 'atmospheric window' bands of 3-5μm and 8-14μm in a huge range of products ranging from fire alarms to intruder detectors, in instrumentation such as gas analysis and laser beam characterisation and in military/paramilitary applications such as thermal imaging. This paper briefly reviews the criteria for the selection of pyroelectric materials and discusses the properties of both bulk materials and thin films in the particular context of their application to uncooled thermal imaging. The present state of development of thermal imaging arrays and cameras based on these materials is also reviewed.