This study investigates the influence of investment in key intangible resources and capabilities of firms, including intellectual capital (IC), financial capability (FC), and corporate social responsibility (CSR) on sustainable competitive advantage (SCA) and firm performance (FP) in an emerging country, Pakistan. The research model and its pertinent hypotheses are tested on a sample of 329 Pakistani small and medium enterprises (SMEs) by a structural equation model (SEM). The results exhibited a significant influence of the aforesaid factors on FP. However, SCA fully mediates the relationship between FC and FP and between CSR and FP, whereas SCA partially mediates the relationship between IC and FP. Taken together, the findings suggest the role of CSR and FC in indirectly spurring FP through SCA. Despite the limitations of this study, the results have several practical and theoretical implications for owners, managers, and policymakers.