This annual report provides a prospective overview of the social dimension in the European Union as a background to social policy development and contributes to the monitoring of developments in the social field across Member States. Furthermore, it establishes links to other Commission publications such as Employment in Europe, Industrial Relations in Europe and the Gender Equality Report. It combines harmonised quantitative information with survey data on public opinion. In 2004 the report seeks to portray the social dimension of the enlarged Union, looking at both developing social trends and emerging policy challenges.