Conventional economic thought classified services as non-tradeables. That convention, which never accurately reflected commercial reality, is now long outdated. It is outdated because the world is interconnected as never before and services have outgrown national borders.
It is also outdated by the WTO's General Agreement on Trade in Services (GATS), which created a new paradigm for international trade in services. The Agreement defined forms of services trade that had previously not been considered, such as commercial establishment, the movement of natural persons, and included the whole range of services sectors.