The special characteristics of narrow-gap semiconductors have long been recognised, not only for their interesting physical effects, but also for their technological applications. Such materials are found across a wide range of elements, compounds and alloys. The International Conference on Narrow-gap Semiconductors and Materials (NIST, Gaithersburg) reviewed past research into the physics of both materials and devices, and summarised the present position, in the light of recent rapid developments in the semiconductor field. This major conference, the first of its kind since 1981, drew together 158 delegates from 14 countries. Invited reviews and invited and contributed papers covered III-VI, III-V and IV-VI compounds and various alloys. Topics considered ranged from the characterisation of artifically structured materials to the physics of infrared detector devices, as well as a review of high-Tc superconductors for infrared detection; this diversity is reflected in the reviews and papers presented here. This book will be of value to all scientists and engineers interested in narrow-gap semiconductors and needing to keep up to date with the rapid advances in this area.