Researchers have suggested that the number of adults holding advanced academic degrees across the population in the United States is falling behind those within the developed nations. Student retention is critical to U.S. colleges and universities’ retention. Retention of in-residence military high school graduates after they enter college is the research problem upon which this study was focused. Understanding the distinct perspective of in-residence military high school graduates can contribute to the improvement of persistence and retention programs for traditional college students; however, a search of the literature revealed an incomplete and unbalanced body of empirical research about this unique population. The purpose of the present study was to describe and evaluate the transition and retention experiences of high school alumni who graduated from an in-residence military school and subsequently attended a 4-year university as an undergraduate student. A qualitative method was implemented with a case study design to explore the perceptions, attitudes, and lived experiences of alumni of in-residence military schools who are freshmen through senior undergraduates attending a sample of diverse 4-year universities across the United States. Participants were alumni from in-residence military high schools and were currently enrolled in traditional 4-year university settings. Elements that enhanced or hindered the retention of military school graduates as they progress or fail in the university setting was explored as well as the role their previous high school experience had regarding their successes or challenges. A semi-structured interview protocol with open-ended questions was implemented to collect data through face-to-face interviews in person where possible or through media such as Skype. Interviews were audio recorded and results were transcribed. Qualitative data requires interpretation and organization into categories to enable construction of a picture by using open coding where themes, patterns, concepts, or similar features can be identified. Therefore, data was separated into categories to search for themes and patterns. Inductive reasoning facilitated the development of conclusions and generalizations.