Social inequality refers to the ways in which socially-defined categories of persons (according to characteristics such as gender, age, ‘class’ and ethnicity) are differentially positioned with regard to access to a variety of social ‘goods’, such as the labour market and other sources of income, the education and healthcare systems, and forms of political representation and participation. These and other forms of social inequality are shaped by a range of structural factors, such as geographical location or citizenship status, and are often underpinned by cultural discourses and identities defining, for example, whether the poor are ‘deserving’ or ‘undeserving’. Understanding the changing patterns, causes and consequences of social inequality in the post-Socialist countries of Eastern Europe, both within and outside of the borders of the European Union, is central to the CEELBAS agenda. This is because comparative evidence from Western Europe and elsewhere in the world suggests a strong link between social inequality and a variety of socio-economic and political ‘ills’. In the sphere of health, for example, high death rates and stress-related illnesses all appear to be closely correlated with high levels of income inequality, as does violent crime. With regard to democratic development, deepening inequalities within and between different groups in society are associated with low levels of social cohesion and participatory citizenship. In addition, social inequality can impede democratic consolidation by stimulating social conflict and political instability, and in turn may act as a support for the establishment of authoritarian regimes. For these reasons, if we are to understand the nature of the societies which are emerging in Eastern Europe, as well as the directions in which they are moving, it is essential that we understand the changing patterns of inequality experienced within those societies.