1 Introduction  
2.1 System and security models  
2.2 The territorial collectivity use case in Europe  
3 Selected criteria  
3.1 User governance criteria  
3.2 Data exchange flow criteria  
4 Taxonomy and list of technical approaches  
4.2 Personal Data Stores  
4.3 Anonymous certificate systems  
4.4 Access-control delegation architectures  
5 Evaluation of the selected solutions  
6 Synthesis  
6.1 Identity managers  
6.2 Personal Data Stores  
6.3 Anonymous certificates  
6.4 Access control delegation architectures  
6.5 Identifying an optimal solution  
7 Future research directions  
8 Conclusion