Summary This paper has dealt in very general terms with the development of an operational-informational point of view in psychology, built upon the structure-of-intellect model, which was derived from an organization of the information-processing abilities or functions found in factor-analytic investigations. The view involves three basic aspects or dimensions—operations (acts), contents (substantive kinds of information), and products (forms)—all of which are important for a complete psychology. It was pointed out that each historical school of psychology placed its emphasis upon one of these aspects, to the general neglect of the other two, even with further self-limitations. Operation psychologies generally dealt with faculties, acts, or functions. Content psychologies described conscious experiences of sensations and feelings, and needed the concept of information to broaden their conceptions of what could be described and thus treated scientifically, even within the scope of the aspect of content. Th...