However, as yet there are no established theories on how inflation expectations should be brought back to the target once they have drifted downward. In particular, we do not have established theories that explain how inflation expectations can be raised at the zero lower bound and that suggest feasible policy measures to achieve this.
This so-called Maastricht Approach is geared to the principle of open markets, a principle that is guaranteed in the single European market by the four fundamental freedoms: free movement of goods, capital, services and people. The Maastricht framework is founded on the principle of subsidiarity, which was enshrined in the treaties of the European Union.