This article by Adam Hanieh features in the World Social Science Report 2016. Social and economic inequalities remain among the most pressing developmental issues for the Arab region. These inequalities are indicated by the large and persistent disparities that exist in ownership and control of economic wealth, access to resources and markets, and the exercise of political power. They are found both within and between states, and have profound and complex connections to violence and conflict. This contribution examines some of the quantitative and qualitative trends in inequality for the Arab world, and explores their relationship to contemporary political dynamics.