Based on Holston's analysis of the modernist principles guiding the planning of Brasilia, and on Vale's analysis of the expression of power and nationalism in high status buildings in third world countries, the paper discusses the validity of modernist assumptions about using environmental design to form life styles compatible with the development of a rational society. While some of the assumptions of the early modernists can be considered erroneous or outdated, the basic idea about spatial organisation having an influence on life styles can not be dismissed, especially not in underdeveloped countries, it is argued.