As part of his employment contract, a worker may be required to perform a temporary assignment in another EU Member State. Such a movement falls within the scope of free provision of services, and not free movement of workers (cf. Rush Portuguesa, ECJ, C-113/89), unlike the situation of a worker who moves independently, hoping to find work in another Member State. This means, therefore, that a German company employing Turkish workers (Turkey being a non-EU country) may legitimately, under a contract to provide services, send its Turkish employees to work in the Netherlands, without each of the workers having to obtain a permit to work on Dutch territory (example taken from Essent, CJEU, C-204/12)

Despite a temporary movement, the employment contract remains, in principle, subject to the law of the home country, i.e. the country where the worker habitually carries out his work, in accordance with Article 8§2 of the Rome I Regulation (N° 593/2008). But as in any contract, parties may also choose the governing law. If this is the case, the chosen law will apply, provided however that the worker is not deprived of the protection afforded to him by mandatory provisions under the applicable law in the absence of choice (Article 8§1). 

This practice of posting workers favors “social dumping”, i.e. a phenomenon consisting in gaining competitive advantage at the expenses of social regulations. Indeed, even within the EU, there is a gap with regards to labor costs and social protection, especially in Eastern Europe where standards are lower. Pursuant to the above-mentioned conflict-of-law rules, it would then be possible to hire foreign workers at a lower wage and with less protective working conditions than the standard practice of the host country, since such workers would remain subject to the law of their home country.


To fight against this phenomenon, the European legislator has implemented (with Directive 96/71/EC, amended by Directive 2018/957/EC, and completed by Directive 2014/67/EU) an obligation to apply to the employment relationship, regardless of the governing law, certain provisions from the legislation of the host Member State which constitute a “nucleus of mandatory rules of minimum protection”. This “hard core”, mentioned in Article 3 of the directive, is made up of rules laid down “by law, regulation or administrative provision and/or by collective agreements or arbitration awards (…) universally applicable” in the following areas: maximum work periods and minimum rest periods, minimum rates of pay, health, safety and hygiene at work, terms and conditions of employment of pregnant women or women who have recently given birth, equality between men and women, among others. However, this provision does not seem to take into account the diversity of the trade union landscape within the EU.

For instance, even though in Italy there are national collective agreements (“CCNL”, contratti collettivi nazionali) signed by the most representative national unions, such agreements do not have erga omnes effect. As far as the remuneration is concerned, Courts have extended the protection relying on Article 36 Cost.  However it is debatable if other rights or conditions set in collective agreements fall within the “hard core” provided for by EU law. Indeed, Article 39 of the Italian Constitution, which establishes the principle of trade union freedom, prevents a collective agreement from being applied to a union that has not signed it or to a non-unionized worker (cf. Naples Court of Appeal, February 3, 2022, n.94). On the contrary, the French case does not cause any particular problem since most collective agreements are not only national (“CCN”, convention collective nationale), but also with erga omnes effect: when a CCN applies to the company, it concerns all employees without exception.

For more information, contact us at the following email address: [email protected]

Marco Amorese

Jeanne Deniau