The purpose of this study was to provide information to an online university that offers Ph.D. programs in three formats: knowledge area modules (or KAM, a type of faculty-led, self-directed doctoral study), course-based model, and mixed model (a combination of the KAM and course-based models). The investigators sought to determine why students choose a particular delivery model; their satisfaction with the model; and if they switch, why they do so. A mixed-method approach was utilized using quantitative student characteristics and survey data as well as qualitative survey and interview data. Results indicate that students enrolled in a course-based online Ph.D. program are more likely to be retained and more satisfied than students enrolled in other online delivery models.