A summary of the book Los principios y normas de armonización fiscal y el Concierto Económico (The Principles and Rules of Fiscal Harmonization and the Economic Agreement) (Fundación BBV, page 179). The work places the Concierto Económico (Economic Agreement) for the Basque Country within the current legal system and compares it to other systems of fiscal decentralization in other countries. It then analyzes each of its harmonization rules.