The unintentional importation and subsequent establishment of subterranean termites in a localised area in Saunton North Devon has provided definitive evidence of the ability of at least one genus of termite to survive in the UK climate and to present a risk to UK buildings. This Digest describes the biology of the termites, their likely significance as potential structural pests in the UK, and gives diagnosis and infestation, recognition and the key principles of termite detection and management. The Digest concentrates particularly on species of the genus Reticulitermes, because this genus is well established in continental Europe and poses the most significant threat to UK buildings and related structures. Part 2 deals with control an management, including colony elimination for eradication purposes.