Information in SIS is shared among the institutions of countries participating in the Schengen Agreement Application Convention (SAAC). The five original participating countries were France, Germany, Belgium, the Netherlands, and Luxembourg. Twenty-one additional countries have joined the system since its creation: Spain, Portugal, Italy, Austria, Greece, Finland, Sweden, Switzerland, Denmark, Iceland, Norway, Estonia, the Czech Republic, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, Slovenia and Liechtenstein. Among the current participants, Iceland, Liechtenstein, Norway, and Switzerland are members of the European Free Trade Area but not of the European Union.