Biological processes in any living organism are based on selective interactions be­ tween particular biomolecules. In most cases, these interactions involve and are driven by proteins, which are the main conductors of any life process within the organism. The physical nature of these interactions is still not well known. This book presents an entirely new approach to analysis of biomolecular in­ teractions, in particular protein-protein and protein-DNA interactions, based on the assumption that these interactions are electromagnetic in nature. This new ap­ proach is the basis of the Resonant Recognition Model (RRM), which was devel­ oped over the last 15 years. Certain periodicities within the distribution of energies of delocalised electrons along a protein molecule are crucial to the protein's biological function, i.e. inter­ action with its target. If protein conductivity were introduced, then charges mov­ ing through the protein backbone might produce electromagnetic irradiation or ab­ sorption with spectral characteristics corresponding to energy distribution along the protein. The RRM is capable of calculating these spectral characteristics, which we hypothesized would be in the range of the infrared and visible light. These characteristics were confirmed with frequency characteristics obtained ex­ perimentally for certain light-induced biological processes.