Terahertz spectroscopy is an exciting field of vibrational spectroscopy which has an excellent potential for the physico-chemical characterisation of materials but it is, as yet, largely under-explored. Recent developments in semiconductor physics have made it possible to provide light at terahertz frequencies (a frequency of 1 THz equals a wavelength of 0.3 mm or a wavenumber of 33 cm 1) in a relatively simple way. This meeting brings together the leading UK researchers in the community to give an introduction into the technology, its applications, the interpretation of the experimental data and an outlook into the future of this important new field of spectroscopy.