This panel unites two empirical, international comparative approaches to the study of the integration of Muslims in Europe. One difficulty common to both approaches is to define a standard against which the integration of Muslims and Islam in Europe can be assessed. The first approach uses micro-level data and addresses the question whether religious identity is decisive for all aspects of integration. The innovative baselines for comparison that are proposed by the first two papers are – for the study of the attitudes of Muslims on socio-cultural key issues – the attitudes of non-Muslims and – for the study of immigrants’ national identification – a measurement of their national identification shortly after arrival. These papers also propose comparisons across countries, Muslim denominations and immigrant groups. The second approach explores how the integration of Islam on the organizational and institutional meso-level is framed by the national macro level, more particularly traditions of state-church relationship, administration or welfare state. Thus here, the search for a baseline turns towards past processes that have defined the place of native Christian communities in the public sphere. One paper explores how the role of Islamic organizations as providers of social services on behalf of the state compares to existing but also changing arrangements for Christians, the other looks at how the regulation of religious accommodation for Muslims in the military compare to regulations for native Christian groups.