Introduction: Social solidarity in Europe: the fourth pillar ~ Marion Ellison; The concept of solidarity in the European integration discourse ~ Józef Niżnik; Solidarity at the margins of European society: linking the European social model to local conditions and solidarities ~ Tomáš Sirovátka and Petr Mareš; Towards a globalisation of solidarity? ~ Menno Fenger and Kees van Paridon; Contested terrains and emerging solidarities within child care law, policy and practice in Europe ~ Marion Ellison; Embedding European identity in context: changing social solidarities in Europe ~ Jim Barry, Elisabeth Berg and John Chandler; Intra-European energy solidarity at the core of the European integration process: future possibilities and current constraints ~ Annamária Orbán and Zoltán Szántó; Social solidarities and immigration integration policies in South-Eastern Europe ~ Anna Krasteva; Normative power Europe: a tool for advancing social solidarity within and beyond Europe ~ Andy Storey; Social solidarity in post-socialist countries ~ Damir Josipovič; Trade unions, NGOs and social solidarity in Romania ~ Cristina Stanus; Social solidarity and preferences on welfare institutions across Europe ~ Béla Janky; Social solidarity, human rights and Roma: unequal access to basic resources in Central and Eastern Europe ~ Richard Filcak and Daniel Skobla; Conclusion: the future of social solidarity in an enlarged Europe: key issues and research questions ~ Marion Ellison.