Ordinary legislative procedure
The general legislative procedure was previously called "co-decision" because Parliament was involved in the legislation and could propose amendments and veto laws.
It is now described in the Lisbon Treaty, Article 294 TFEU, and is the main rule for laws to be adopted in the EU. In practice most laws are decided by informal agreements between representatives of the three institutions.
There were nearly 1,000 such confidential Trialogue Meetings in 2013, and 80% of the laws in that year were dealt with a in a single reading and ended up as first-reading agreements.
See Trialogue Meetings and Tripartite Agreements
The formal ordinary legislative procedure:
· The EU Commission has the sole right to propose new EU laws.
· Council then usually adopts the Commission's proposal by a qualified majority.
· Parliament can veto a law or propose amendments by an absolute majority of its members in a second reading. First readings only require a simple majority for amendments.
· If the Council does not accept the amendments proposed by the absolute majority of the members of the European Parliament, a more formal Conciliation Committee is established.
· The result of this Conciliation Committee must be accepted by a qualified majority in the Council and a simple majority in the European Parliament. Otherwise the proposal falls and the process may start again if the Commission should decide that.
Links
Shared decision making http://ec.europa.eu/codecision/index_en.htm
See also the Convention working group on simplification (simplification)