Many argue that the pillar structure, which was maintained by the Treaty, is overcomplicated; that the separate Treaties should be merged into one Treaty; that the three (now two) separate legal personalities of the Communities should be merged; and that the European Community and the European Union should be merged, with the European Union being endowed with legal personality.
Moitos argumentan que a estrutura de piares, que se mantivo no Tratado, é demasiado complicada, que os diferentes tratados deberían fusionarse nun, que o tres (agora dous) personalidades legais das Comunidades deberían fusionarse e que a Comunidade Europea e a Unión Europea deberían fusionarse nunha única Unión Europea cunha única personalidade xurídica.