The rules for temporary mobility are set out in chapter II of Directive 2005/36/EC. The rules apply to the temporary or occasional nature of activities of a self-employed or an employed person in another EU country.
The host EU country:
assesses the temporary mobility on a case by case basis (duration of activity, frequency, regularity, continuity)
may check the professional qualification before the professional can provide services for the first time. This applies when the profession in question has public health or safety implications and does not benefit from automatic recognition under Chapter III of the Directive;
may provide for automatic temporary registration or pro forma membership on the basis of the declaration made in advance;
may require the service provider to supply the recipient of the service with certain information;
requires the professional to inform the public social security bodies in advance or, in an urgent case afterwards, of the services provided.