Summary findings are presented on research about the impact of college in order to identify key issues related to understanding the lives of individual students. Five perspectives are offered: Bowen's outcomes and goals; Feldman and Newcomb's student personality, values, and beliefs; Pace's achievement testing; Astin's longitudinal studies; and Pascarella's cognitive development in social contexts. Theoretical and methodological issues are discussed that set the stage for introducing new ways of explaining the impact of college, and theoretical models are introduced that are influenced by the heuristic orientation of cognitive psychology (Cantor and Kihlstrom's social-cognitive personology theory, and Baron's personality and intelligence theory). It is concluded that the impact of college on students is mediated, influenced, or determined by interactions between diverse psychological processes. Depending on the theoretical orientation of the research, they have been labeled student involvement, openness to change, and quality of student effort. (LB)