This article examines the intermediary role of internal knowledge-sharing in the relationship between two aspects of small and medium-sized enterprises’ (SMEs) internal organisational context: structural and relational interdependence and their entrepreneurial orientation (EO). With a sample of 146 SMEs, the structural equation modelling results show that higher levels of internal knowledge-sharing associate with stronger EO, and that such knowledge-sharing derives from higher levels of task and reward interdependence, as well as from higher levels of social interaction and trust. The findings also reveal that internal knowledge-sharing fully mediates the relationships between SMEs’ task interdependence and trust with EO. The article contributes to research by highlighting several features of SMEs’ internal environment that can be used to enhance their entrepreneurial postures.