This study empirically analyzed the determinants of a strategic alliance's stability based on the framework of game theory. We derived motivational cooperation (voluntary cooperation) and structural cooperation as management logics within strategic alliances and examined which approach is more effective. We analyed the data from the questionnaires obtained from 55 international joint ventures that had gained ground in 9 advanced countries. The results suggested that motivational cooperation (voluntary cooperation) has a stronger influence on the stability between partners than structural cooperation. As a new discovery, the study suggested that motivational cooperation (voluntary cooperation) and structural cooperation have a trade-off relationship