Institutional shortcomings of the Third Pillar: efficiency, effectiveness, complexity, legitimacy – Genesis of the provisions of the Treaty of Lisbon – Communitarisation of the Third Pillar – Some special institutional arrangements – Quid pro quos: stricter delimitation of the Union competencies and extension of the ‘opt out/opt in’ regimes – (New) foundations for Europol, Eurojust and the European Union Prosecutor's Office