The oil-rich member states of the Gulf Cooperation Council (GCC) attract large numbers of migrant workers. The reported rates of psychiatric morbidity among these migrant workers are higher than among nationals, while the mental health services in the GCC countries remain inadequate in terms of both staff and service delivery. The multi-ethnic origin of migrants poses considerable challenges in this respect. The development of mental illness in migrants, especially when many of them remain untreated or inadequately treated, results in their premature repatriation, and the mentally ill migrant ends up facing the same economic hardships which led to migration in the first place. The availability of trained interpreters and transcultural psychiatrists, psychologists and social workers should make psychiatric diagnoses more accurate. Suitable rehabilitation services are also needed.