As a rule, the workers and their employers are subject to the legislation of the country where the activity is performed.
However, several exceptions may occur, being the most common situation that of a worker who is sent by his undertaking to another country to perform temporary work there for that undertaking.
Each State shall define the meaning of temporary and establish whether or not the worker and the sending undertaking shall compulsorily remain subject to the respective social security system, taking namely into account social security international instruments that may exist binding the States concerned.
In Portugal the Centros Distritais de Segurança Social are responsible for processing the claims and the Departamento de Acordos Internacionais de Segurança Social is responsible for the authorisation.
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