Infrared astronomy has undergone an enormous revolution during the last decade. Despite the great technical difficulties of building detectors in a cryogenic environment, the scientific advances in infrared astronomy have been astounding. In the near future many more advances can be expected from still newer developments in telescope and detector designs. High quality detector arrays and passively cooled telescopes are very promising techniques for achieving considerably larger apertures. This volume contains the refereed papers from the workshop on 'Next Generation Infrared Observatory', dealing with all new aspects of future infrared telescopes.