Unveiling the Moderated Mediation Channel of Intellectual Capital in Linking Sustainable Leadership with Sustainable Performance: Evidence from Vietnam’s SMEs

This study investigates how sustainable leadership (SL) affects sustainable performance (SP) among Vietnamese small and medium-sized enterprises (SMEs). It further extends the mediation of organizational learning (OL), moderated by intellectual capital (IC). The study aims to clarify how sustainability-oriented leadership practices can be reinforced through learning mechanisms and intangible resources. Grounded in the natural resource-based view (NRBV) and OL theory, this study analyzes survey data from 498 SMEs using structural equation modelling and the Hayes PROCESS Macro for moderated mediation analysis. The results reveal that SL has a positive effect on SP, with OL mediating this relationship. This underscores the role of continuous learning processes in transforming SL into superior performance outcomes. Among the three IC dimensions, only relational capital (RC) exhibits a significant moderating effect, strengthening both the direct and indirect paths between SL and SP through OL. Meanwhile, human capital and organizational capital show no moderated-mediation effect. These findings suggest that resources of RC play a critical role in leveraging leadership and learning for SP, offering a more nuanced extension of NRBV in the SME context.