This monograph explores recent theory and research on the importance of student effort and involvement in college activities as decisive elements in promoting positive college outcomes. An opening section introduces the issue and is followed by a section outlining the fundamental work of Robert Pace who found that college outcomes depend on responsible student behavior and that environments may either encourage or discourage active student participation. The next section reviews the work of Vincent Tinto, Alexander Astin, and Ernest Pascarella and examines research trends in the past decades in this area. The following section offers summary and retrospective of research on student background. The next section considers the interrelationship between the college environment, what students do while enrolled, and outcomes. This section also covers institutional size and type, residential and commuter institutions, the college environment, institutional and individual fit, and qualitative approaches. The next section addresses how student investment is crucial to college work from the Tinto, Pascarella, Astin, and Pace perspectives. A final section examines implications for practice and inquiry and calls for a new relationship between institutions and students. An appendix lists the 14 quality of effort scales in the College Student Experience Questionnaire. A subject index is included. Contains 102 references. (JB)