Terry was one of the pioneers of the use of neutron scattering in the United Kingdom and a founder member of the BCA. Although interested in many areas of crystallography, his particular specialities are neutron scattering studies of crystal structures and lattice dynamics of inorganic materials. Recent interests are the determination of the crystal structures of the oxides of uranium and the nature of the phase transitions in U4O9. The oxide studies are undertaken in collaboration with Frederico Garrido of the University of Paris, Lech Nowicki of the Soltan Institute of Nuclear Physics, Warsaw and Alberto Albinati of the University of Milan.
The author of a number of highly regarded books, there is a prize awarded in his honour sponsored by the Institute of Physics and the Royal Society of Chemistry.