This qualitative study examined the experiences of Saint Mary’s High School alumnae from the freshman class of 1949 through the graduating class of 2010 in order to identify what has sustained the school over the decades. Years after graduation, alumnae held memories of their school experiences that resulted in personal and long-lasting qualities that continue to have significant impacts on individuals and the institution. Data was gathered through written journals and interviews. The Appreciative Inquiry (AI) model was used to analyze the context of alumnae experiences. Using the AI model, multiple categories arose as positive notables mentioned by the participants. The prominent themes contributing to school sustainability were pastoral care, mission, tradition, and community. These sustaining characteristics, which are still exhibited in the lives of current laity and students, were linked to the original charism brought to the school through the Sisters’ order. Student success and satisfaction are critical to sustaining Catholic schools as tuition continues to rise and enrollment in Catholic schools’ decline. Saint Mary’s High School, and other similar Catholic schools, should consider strengthening their identity through mission-related activities and values. The findings of this study suggested that sustaining Catholic school environments may be as simple as becoming reacquainted with their original missions. Results of this study showed that Catholic school leaders and faculty are successfully transmitting the same values and mission-driven messages as their predecessors. Emphasizing a holistic and compassionate school setting is vital to the overall success of each student and the longevity of schools.