The right of persons to move freely within the EEA is complemented by a system that coordinates social security schemes. The co-ordination system lays down common rules and principles determining which national legislation applies in each case, in order to avoid migrant workers being insured either twice or not at all.
The coordination system covers sickness and maternity, accidents at work, occupational diseases, invalidity benefits, old age benefits, survivors’ benefits, death grants, unemployment benefits and family benefits.
The social security provisions foresee that the social security legislation of the host EEA State extends the rights and obligations of its own nationals to nationals of other EEA States residing on its territory. A person who moves from one EEA State to another may not be placed in a worse position than a person who has always resided and worked in the same EEA State.
The European Commission's Directorate-General for Employment, Social Affairs and Equal Opportunities: