This article examines relationships among top-management-team composition, group processes, and the effects of those processes on cohesion for international joint venture (IJV) teams in Thailand. For culturally diverse teams, demographic elements (member age, length of team tenure, level of education, functional expertise) and cultural characteristics (country of education, nationality, affiliation with a parent organization, primary language spoken) define heterogeneity. Overall, demographic heterogeneity had a significant influence on openness among team members and on cohesion when mediated by openness. Cultural heterogeneity had a significant influence on openness and cohesion among team members, with the dimensions of trust (loyalty and openness) having a significant influence on cohesion.