The European Commission represents the interests of the EU as a whole. It proposes new legislation to the European Parliament and the Council of the European Union, and it ensures that EU law is correctly applied by member countries. The term 'Commission' refers to both the 27 Commissioners (28 after Croatia's accession on 1^stJuly 2013) and the wider institution itself.

The Commission has the right of initiative to propose laws for adoption by the European Parliament and the Council of the EU (national ministers). In most cases, the Commission makes proposals to meet its obligations under the EU treaties, or because another EU institution, country or stakeholder has asked it to act. From April 2012, EU citizens may also call on the Commission to propose laws.

Before making proposals, the Commission consults widely so that stakeholders' views can be taken into account. In general, an assessment of the potential economic, social and environmental impact of a given piece of legislation act is published along with the proposal itself.

The principles of subsidiarity and proportionality mean that the EU may legislate only where action is more effective at EU level than at national, regional or local level, and then no more than necessary to attain the agreed objectives.

Once EU legislation has been adopted, the Commission ensures that it is correctly applied by the EU member countries.