Abstract
ESG requirements increasingly shape access to export markets, yet exporting SMEs show striking heterogeneity in how they build ESG commitment systems. Drawing on microfoundations, we treat this variation as a conversion problem: managerial competence and resource slack create latent capacity for ESG-related change, but this capacity must be converted into a coherent ESG strategic posture through relational governance capability. We test the model with using primary survey data from 200 Polish exporting SMEs. Regression analyses with bootstrapped indirect effects show that relational governance capability is positively associated with ESG strategic posture and fully mediates the associations of managerial competence and slack with posture. The findings indicate that for resource-constrained exporters, internal endowments alone are insufficient and that boundary-spanning competencies that support trust, knowledge exchange, and joint problem solving help translate capacity into buyer-legible ESG commitments. For international business practice and policy, the results suggest that exporters should invest in relationship-governance routines alongside internal resources, and that international buyers can reduce supplier exclusion by coupling ESG requirements with implementation support and relational safeguards.