This report on "Payment and securities settlement systems in the European Union" is the fourth edition of what has become known as the "Blue Book". The first edition was published in 1992 by the Committee of Governors of the Central Banks of the Member States of the European Economic Community as a description of the payment systems of the then 12 Member States of the European Community. The second edition was published by the European Monetary Institute in April 1996, and the third edition was produced by the European Central Bank (ECB) in June 2001. This fourth edition takes account of the fundamental changes in payment and securities settlement systems which have taken place in the period from 2001 to 2007.