This study was carried out to establish the possibility of enhancing SME sustainability in Kampala, Uganda through boosting key internal drivers of entity performance (records management, internal communication, family influences, and online presence). Using conclusive, cross-sectional, and case study research designs supported by the philosophical underpinnings of critical realism and positivism epistemology, data was collected from 278 SMEs using semi-structured questionnaires. Using SEM analysis, it was revealed that all the key drivers have a positive significant statistical effects of the sustainability of SMEs (records management [S.E = 0.3; p = 0.000], internal communication [S.E = 0.229; p = 0.017], family influences [S.E = 0.162; p = 0.041], and online presence [S.E = 0.321; p = 0.000]). It was therefore recommended that key internal success factors identified need to be considered in the management and operations of SMEs in Kampala. This is aimed at guaranteeing the sustainability of SMEs and the boosting of the private sector.