A rigorous study of the interactions between DNA and proteins or other molecules requires the accumulation of a wide range of information regarding the nature of such an interaction, Among the parameters on which it is desirable to gain information are: the size and number of the binding site(s) on the nucleic acid in question, the sequence specificities of the binding events, the strength of the interaction, the biochemical effects of the binding, and the structural consequences of such an interaction on all the molecules concerned.