Without doubt, an under-used tool is "Enhanced Cooperation" (defined in Article 20 TEU). This procedure was used for the first time in the area of divorce and legal separation and subsequently for the creation of unitary patent protection in the EU, as well as the proposed introduction of a financial transaction tax. Secondly, the "Passerelle" (bridges) clause (i.e. Article 48(7) TEU), may be used. However, such revisions would require unanimity among the governments of Member States in the European Council or Council, which may be difficult to implement. Both these tools could, in principle, simplify and speed-up European decision-making.