The European Parliament (Photo: corporate.computershare.com/uk/Forefront_News)

When national laws are harmonised they are made consistent across the EU. Before the Single European Act in 1987, harmonisation of laws required unanimity. Now, most harmonisation rules can be decided by a qualified majority.

The future

The EU Constitution introduces the possibility for a qualified majority to harmonise EU law in sensitive areas. In the most sensitive areas, so-called, 'bridges' or 'passerelles' allow the EU to introduce the use of qualified majority voting if this is agreed upon unanimously by the European Council.

However, there are areas, such as culture and education, within the areas of supporting, coordinating and complentary action listed in article 1.16 of the EU Constitution, for which national laws cannot be directly harmonised.