We review the theoretical and empirical economic literature upon income inequality in emerging countries. We firstly describe the main observed de velopments and show that these are rather diverse across countries and developing regions. We subsequently expose the main theoretical mechanisms. We make a distinction between the traditional approaches (Kuznets, Lewis, Stolper-Samuelson) and the new explanations. In the latter, globalization and globalization-driven technological changes are at the core of the analyses. Both approaches bring out several opposite mechanisms. Finally, the empirical estimates display rather conflicting results. Most cross-country studies find a weak impact of globalization on income inequality. In contrast, several longitudinal studies concerning countries taken separately or small groups of countries reveal a positive correlation between openness and the relative demand for skill and inequality. These apparently conflicting findings reflect the opposite mechanisms linked to globalisation and the differences in countries' experiences.