There should be at least one, but better yet, a series of international districts with sizes of up to 100 square kilometers each that would serve as locations in which to headquarter international organizations such as the UN, WTO, the International Red Cross, international courts, and others. Each of these districts could be located in different major geographical/cultural regions of the globe (North America, Latin America, Sub-Saharan Africa, North Africa/Southwest Asia, Europe, Asia, Oceania, etc.).
In addition to each location perhaps headquartering different international organizations, they could also serve to headquarter regional organizations, like the OAS, CIS, OAU, APEC, AL, ASEAN, etc.
Organizing such significant international institutions in this manner would diminish the perception of inequality, and even racism, among various global groups than would otherwise be the case if such organizations were based almost exclusively in the United States, Europe or other areas historically viewed as being large scale domineers.