Each WTO member is required under the GATS to have a services Schedule, in the same way that they had a tariff Schedule under the GATT. Taking a glance at any services Schedule, you will notice that it is quite different from the goods Schedule. It has four columns, fewer than most goods Schedules, but this does not make it less complex. In fact, a services Schedule may prove more challenging to read and interpret. While a goods Schedule, in its simplest form, lists only one tariff rate per product, a services Schedule contains at least eight entries per sector. The commitments on any Scheduled sector are recorded with respect to four modes of supply and two types of actual or potential restrictions: ‘limitations on market access’ and ‘limitations on national treatment’.

The four modes of supply correspond to the definition of trade in services in Article I:1 of the GATS. They consist of: cross-border supply (mode 1), consumption abroad (mode 2), commercial presence (mode 3) and presence of natural persons (mode 4). The limitations inscribed with respect to these four modes often relate to domestic policy interventions, such as restrictions on foreign investment, on the form of legal incorporation or on the scale of business operations, which go far beyond border measures and usually target suppliers rather than services.