Spectral scanning is accomplished in an electronic scanning spectrometer by means of a television-type camera tube called an image dissector. Since the scanning is done electronically, extremely rapid spectral scanning can be performed without any mechanical movement. The standard instrument has selectable scan rates of 100 or 1000 spectral scans per second, although faster and slower scan rates are possible. The sensitivity of the spectrometer is the same as a conventional mechanical scanning spectrometer using a photomultiplier detector if it were possible to scan the latter at the same high rate. The instrument is being used to investigate the time variation in spectral output of light sources, but should also be useful in other studies such as explosions, shock tubes, lightning, plasmas, missile launch and reentry, and other sources of intense transitory radiation phenomena.