Population ageing of most Western post-industrial societies, global integration of business, and important migration flows have brought many work organizations to hire cross-national and multicultural work teams. In this context, it seems relevant to study the influence of certain individual and cultural characteristics on the process of professional integration. 623 participants (398 Swiss workers and 225 foreigners working in Switzerland) completed the NEO-Five-Factor Inventory, the Utrecht Work Engagement Scale, and the General Work Stress Scale. Our results show that the national workers’ levels of work engagement and job stress appear to increase with age, while they decrease for migrant workers. In addition, work engagement was negatively associated with neuroticism and positively with the other four personality dimensions. Finally, job stress was positively associated with neuroticism and conscientiousness, and negatively with extraversion. However, the strength of these relationships seemed to vary according to the worker’s nationality, age, gender, education or income.