Abstract :
Mid- and far-infrared spectroscopy and photometry for many newborn and dying stars, which very often are hidden in thick and opaque clouds, has become possible with the advent of the Infrared Space Observatory (ISO). In this review I present the most important results obtained with the Infrared Space Observatory as far as the initial and final stages of stellar evolution are concerned. These achievements are based on observations made by all four instruments on board the ISO satellite, with emphasis on data from the spectrometers.
