Recent research reveals strong effects of involvement in international organizations on state policies, but much of this research downplays inequality in world political participation, and there is only a limited understanding of what explains world-polity ties. Using data on memberships in intergovernmental and international nongovernmental organizations (IGOs and INGOs) for 1960 through 2000, this study analyses inequality in the world polity. IGO ties are fairly evenly distributed, but the level of inequality in INGO ties is as high as the level of world income inequality. Since I960, inequality in ties to IGOs decreased sharply, but inequality in ties to INGOs remained more stable. A conflict-centered model of the world polity is developed here that explains world political participation as a function of material and symbolic conflict. Rich, core, Western states and societies have significantly more ties to the world polity than do others. Powerful states dominate IGOs less now than they did in 1960, but rich, core, Western societies have grown more dominant in the INGO field.