This paper aims to shed light on the relationship between the entrepreneurial behaviour of small and medium‐sized enterprises (SMEs) and their commitment to sustainable development (SD). In order to analyse the determinants of SD engagement at the organisational level, we draw on the resource‐based view of the firm and examine specifically the effects of entrepreneurial orientation and internationalisation, using survey data from Spanish and Mexican SMEs. Our results reveal that entrepreneurial orientation is positively associated with SD engagement, particularly regarding the environment, human resources, and community involvement. However, we could only observe a positive effect of SME internationalisation on SD engagement in Mexican but not in Spanish firms, suggesting that this effect is context‐dependent and related to institutional pressures. We discuss the implications of these findings for scholars and practitioners. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment