The EEA includes the 27 member states of the EU and 3 of the four European Free Trade Association (EFTA) states. These are Iceland, Liechtenstein and Norway.
Switzerland, also an EFTA state, signed the EEA agreement but did not join. This was after a national referendum rejecting the ratification. Instead, Switzerland has a series of bilateral agreements with the EU.
Within the EEA, the main freedom of movement still applies. However, the agricultural or fishery policies do not apply to the EFTA states.
The EFTA states are not represented in the Institutions of the European Union.