»European Union Law and Constitutional Limitations on Data Mining by the Federal Security Authorities«: Data mining technologies facilitate the detection of patterns and correlations within extensive data sets. By reason of the inherent encroachment upon the fundamental rights of the individuals concerned, statutory provisions governing automated data analysis are subject to constitutional scrutiny. This study analyses the requirements under European Union law and the German Basic Law pertaining to the utilisation of data mining by the federal security authorities. In conclusion, the author tenders a legislative proposal.