Social and individual spending on higher education has outpaced social and individual economic growth, resulting in nonprofit institutions of higher education (NIHEs) growing increasingly dependent upon unsustainable governmental subsidies and tuition increases. The purpose of this study was to examine the interactions among components of the nonprofit university system, existing revenue generation methods, and sustainability of revenue generation, thereby generating a new sustainable revenue theory for nonprofit universities within the United States. This qualitative grounded theory study used a multiphase design incorporating data from the literature review, historical documents, and phone interviews from a theoretical sampling of 10 NIHEs. Participants were 20 faculty, 40 students, 40 administrative staff, and 20 members of the business community. Analysis included open, focused, axial, and theoretical coding. The study's findings theorize that a sustainable revenue generation system must continually include, and respond to, the multidirectional interactions of all system components as they change over time, including businesses. The result of the multidirectional connectivity between all of the system components was increased revenue for NIHEs and reduced student and government-funded tuition. Additionally, an organizational culture that is incongruent with change has been identified in NIHEs and must be mitigated. The findings of this study could positively affect NIHEs by providing a sustainable and adaptable system for improving revenue generation while increasing affordability and accessibility for students of these institutions, which, in turn, may produce positive social change.