The configuration of the detectors in the Long Wavelength Spectrometer (LWS) flown on the Infrared Space Observatory (ISO) satellite is described. The results of sensitivity and spectral response measurements on prototype detectors and filters are outlined. Spectral response profiles are presented for various stressed and unstressed detectors. Dark current versus 1/T response for three detectors is shown in graphic form. The signal flow diagram for detector tests is presented
