Depending on the issue, the EU has many different ways to make a decision. In most cases, the Council must come to an agreement with the European Parliament, on the basis of a proposal from the Commission. This applies to issues such as free movement between the Member States, environment, transport, research, the euro and customs cooperation. To put it simply, the EU usually makes decisions in the following way:
1. The Commission presents a proposal.2. The European Parliament and the Council discuss the proposal.3. The Council takes a decision, sometimes together with the Parliament.
The codecision procedure is the most common way to make this type of decision. This means that both the Council and the Parliament can amend the Commission’s proposal, and that both institutions must agree for the proposal to be accepted. This is the process in which the European Parliament has greatest influence over the substance of a decision. In other cases, the European Parliament only has the possibility to give its opinion of the Commission’s proposal, without the Council being obliged to follow what the Parliament says.
For cooperation on the EU's Common Foreign and Security Policy and on policing and criminal law, the Member States have not handed over the power of decision to the EU. Decisions are made chiefly by means of negotiation in the Council and resemble international agreements. The European Parliament has little or no influence.