In the XXth century, some of the emerging environmental agreements were
designed to include powerful economic incentives. At the same time,
environmental commitments started to enter treaties on trade. This led
to the potential for a conflict between environmental measures limiting
trade and GATT/WTO norms protecting the free market. Besides, the
emerging environmental crisis triggered the debate about incorporation
of environmental values at the WTO level. The issues were a subject of
discussion at GATT/WTO for decades. Meanwhile, regional trade
arrangements prepared a platform for obligations under environmental
treaties to be compatible with free trade. These arrangements are
examined as legal instruments suitable to reconcile both trade and
environmental values.