Even if postal and courier services represent traditional means of communication, they remain essential to a country's economic and social development, even in today's information society, where new communication technologies keep emerging. Nevertheless, these services have been transformed in many aspects in order to face the challenges resulting from the IT revolution.

Traditionally, the postal sector has been characterized by state-owned monopolies providing basic mail services and privately owned courier companies supplying parcels and providing expedited mail services. This traditional picture is also reflected in how the sector was initially approached in the GATS: the Services Sectoral Classification List makes a distinction between postal and courier services on the basis of the nature of the service providers rather than that of the services provided. Today, such a distinction is put into question by the radical change the sector has experienced across the world over the last twenty years.

Since the 1990s market-oriented postal reform has been undertaken in most countries: public postal operators have been corporatized and/or privatized, and the scope of postal monopolies has been reduced or even completely abolished. The structure of the industry is changing, and in many cases the boundary between public and private operators is blurring. Moreover, actively responding to the new business environment, both traditional postal operators and private delivery companies are using new technologies and expanding into new business areas. At the same time, new regulatory issues have arisen as a result of the liberalization of postal markets.