RESUMO
This paper examines the relationship between 'world citizenship' and the new psychiatric research paradigm established by the World Health Organization in the early post-World War II period. Endorsing the humanitarian ideological concept of 'world citizenship', health professionals called for global rehabilitation initiatives to address the devastation after the war. The charm of world citizenship had not only provided theoretical grounds of international collaborative research into the psychopathology of psychiatric diseases, but also gave birth to the international psychiatric epidemiologic studies conducted by the World Health Organization. Themes explored in this paper include the global awareness of mental rehabilitation, the application of public health methods in psychiatry to improve mental health globally, the attempt by the WHO to conduct large-scale, cross-cultural studies relevant to mental health and the initial problems it faced.