In this book we investigate the physics and technology of modern superconducting detectors in view of their employment in millimetre and submillimetre receivers that require high performance such as astronomical telescopes. The book presents an in-depth description of the physics of these detectors and also how they can be designed and integrated in the receiver, in the frequency range from 100 GHz to 1.5 THz. Our discussion covers the device physics and the detector chip design that couples the signal to the detector. Both coherent detection using superconducting mixers and total power detection using bolometers are covered.