This excerpt taken from the BBV 20-F filed Apr 2, 2009.
The integration of Spain into the EMU on January 1, 1999 implied the yielding of monetary policy sovereignty to the ESCB. The ESCB is composed of the ECB and the national central banks of the 16 member countries that form the EMU (Slovakia joined the Monetary Union on January 1, 2009).
The ESCB determines and executes the single monetary policy of the 16 member countries of the EMU. The ESCB collaborates with the central banks of member countries to take advantage of the experience of the central banks in each of its national markets. The basic tasks to be carried out by the ESCB include:
In addition, the EU Treaty establishes a series of rules designed to safeguard the independence of the system, in its institutional as well as in its administrative functions.