The possible upgrade of LHC or a future generation of colliders at the extreme limits of energy and luminosity will require detectors based on very advanced technological solutions to fully exploit the physics opportunities offered. Major steps must be taken to design and realize devices that are able not only to handle very high rates but also to cope with the very harsh radiation environment without suffering any performance degradation. This book reviews the present status, current limits and recent developments in detection techniques and related aspects (simulation, signal acquisition, tracking, particle identification, etc.). Novel ideas in this domain are discussed with emphasis on the directions in which improvements in proven techniques are desired.