National parliaments influence national input legitimacy at the European level on European issues through directly entering into the European decision-making and interacting with the European institutions participating in it. To be able to make use of this possibility, they have to devise instruments of cooperation and coordination and learn to use them effectively.
This paper examines the cooperation, or, at least, information exchange among national parliaments on a number of legislative proposals - those chosen for coordinated tests of subsidiarity by national parliaments themselves, those most voted on in the Council of the European Union (EU) and those subjected to three readings in the co-decision procedure - discussed between May 2004 and the entry into force of the Lisbon Treaty. It shows that national parliaments face mmany difficulties in this area, but they increasingly use the cooperation channels available to them.