Electromagnetic energy is an important factor in the biophysical analysis of the properties and function of living systems. Due to technical advances in electronics, this energy is now being used as a research tool, both by study of its emission by living organisms and also by applying it to the organism. In this paper, the nature of the energy is sketched. Then, data on fingertip detection of color, neural emission of infrared energy, the use of electron paramagnetic resonance techniques to detect neural activity, brain impedance shifts and behavior, and the influence of UHF energy on behavior are considered. It is concluded that, though these areas are in the embryonic stage of development, most are potentially of great significance in the understanding of the nervous system and behavior. (2 p. ref.)