Alliances may be an important tool for overcoming the resource and capability deficiencies facing small and medium-sized enterprises (SMEs), as they help strengthen their market position and facilitate access to new markets. In this paper we focus on domestic joint ventures (JVs) for export purposes. Our aim is to analyze the influence of partners' long-term orientation on their commitment, while looking into the key antecedents of long-term orientation: complementarity of partners' resources and trust. The hypotheses set forth are tested on a sample of 70 Spanish domestic export JVs. The data were analyzed using partial least squares (PLS) analysis. Our paper contributes to the literature on export JVs and SMEs by providing evidence that long-term orientation reinforces commitment to devoting the necessary resources and efforts to enable the export JV to succeed. The results also indicate that trust decisively determines the long-term orientation of the partners to an export JV, and that complementarity of resources plays a relevant role in the development of long-term orientation by facilitating trust.