Sustainable development is a process which aims to reconcile economic development with the protection of social and environmental balance.
The inclusion of environmental issues in the definition and implementation of other European policies (energy, research, industry, agriculture, etc.) is essential for achieving the objective of sustainable development. This principle was introduced by the Treaty of Maastricht and in the Cardiff Summit in 1998 and formed the cornerstone for coordinated action at European level.
Following this, in May 2001, the EU adopted a strategy in favour of sustainable development. It was revised in 2006 to remedy its noted shortcomings and to give it new impetus. Furthermore, the global partnership for sustainable development, adopted by the Commission in 2002, gave it an external dimension.
The Lisbon Treaty states that from now on sustainable development shall be included in the European Union's objectives (article 3 & 3 of the Treaty on the European Union).