In the eyes of many, one of the most challenging problems of the information society is that we are faced with an ever expanding mass of information. Selection of the relevant bits of information seems to become more important than the retrieval of data as such: the information is all out there, but what it means and how we should act on it may be one of the big questions of the 21st century. If an information society is a society with an exponential proliferation of data, a knowledge society must be the one that has learned how to cope with this. Profiling technologies seem to be one of the most promising technological means to create order in the chaos of proliferating data. In this volume a multi-focal view will be developed to focus upon what profiling is, where it is applied and what may be the impact on democracy and rule of law. The book is the result of research conducted within the framework of the FIDIS (Future of Identity of Information Society) NoE (Network of Excellence).