Citizens are increasingly crossing borders within the European Union (EU). Europeans have always been free to travel to receive care abroad, but if they wished to benefit from their statutory social protection scheme, they were subject to their local or national legislation on social protection. This changed in 1991 with the European Court of Justice defining healthcare as a service, starting a debate on the right balance between different principles in European treaties: movement of persons, goods and services, versus the responsibility of member states to organise their healthcare systems. Simultaneously, cross-border cooperation has developed between member states. In this context, patient mobility has become a relevant issue on the EU's agenda. The EU funded a number of Scientific Support to Policies (SSP) activities within the Sixth Framework Programme, to provide the evidence needed by EU policy makers to deal with issues that European citizens face due to enhanced mobility in Europe. One SSP project "Methods of Assessing Response to Quality Improvement Strategies" (MARQulS), focused on cross-border care. It aimed to assess the value of different quality strategies, and to provide information needed when: (1) countries contract care for patients moving across borders; and (2) individual hospitals review the design of their quality strategies. This article describes the European context related to healthcare, and its implications for cross-border health-care in Europe. The background information demonstrates a need for further research and development in this area.