Pillars
The Treaty of Maastricht, which established the European Union, structured the EU in three pillars which are now abolished by the Lisbon Treaty:
Matters within the latter two pillars were gradually shifted from the national to the supra-national level, with the result that they became gradually governed by EU law.
The Lisbon Treaty abolished the 3-pillar structure entirely. The principles of Community law established by the European Court will e.g. then also be applicable to the area of justice and home affairs.
Furthermore, as legislative community acts will be adopted in the frame of JHA, the Court will have unrestricted jurisdiction in that area.
For foreign policy the Court's jurisdiction is extended but remains limited. The Lisbon Treaty will merge the three pillars and provide the European Union with a single legal personality in Art. 47 TEU.
The EU is now a full international actor in its own right, capable of concluding international agreements with third countries and international organisations within areas where the EU has internal legislative competence (i.e. areas where the EU currently may legislate on behalf of member states).
Links
Full text of the Treaty of Maastricht: http://eur-lex.europa.eu/en/tr......ies/dat/11992M/htm/11992M.html