Secondment under Dutch employment law
Secondment (detachering) refers to an arrangement whereby an employer temporarily makes an employee available to work for a third party (the client or host organisation) while the employment relationship with the original employer continues. The legal basis is the detacheringsovereenkomst between the employer and the client, supplemented by a clause or addendum to the employee's employment contract consenting to the secondment.
Secondment differs fundamentally from temporary agency work. In agency work the employer's core business activity is placing workers. In secondment, the employer's core activity is providing expertise or services - the seconded employee represents the employer's capacity. Dutch courts and the tax authority (Belastingdienst) apply a substance-over-form analysis to ensure arrangements are correctly classified.
Employee's rights during secondment
Throughout the secondment, the seconded employee remains employed by the original employer and retains all contractual rights: salary, annual leave, pension accrual, and dismissal protection. The host organisation does not become the employer. The employer remains responsible for complying with Book 7 of the Dutch Civil Code, including the duty of care under Article 7:658 with respect to the working conditions at the host's premises.
The employee must consent to the secondment - either in the original contract or separately. A unilateral order to take up a secondment may be challenged if it constitutes a material change to the employment conditions. The employer must demonstrate a legitimate business interest and act in accordance with the principles of good employer practices.
Cross-border secondment and the WagwEU
For employees posted to the Netherlands from abroad, the Posted Workers in the European Union (Enforcement) Act (Wet arbeidsvoorwaarden gedetacheerde werknemers in de Europese Unie, WagwEU) applies. This Act ensures that posted workers receive the minimum employment conditions applicable in the Netherlands, including minimum wage, working hours, and health and safety rules, regardless of the law applicable to their employment contract.
Under Article 7:690 of the Dutch Civil Code, which governs the temporary agency contract, the law distinguishes the secondment arrangement from agency work on the basis of the employer's core business activity. Dutch courts and the tax authority apply a substance-over-form test: if the employer's predominant activity is placing workers rather than providing expertise, the arrangement may be reclassified as agency work. Notably, the Supreme Court has ruled that a secondment contract cannot tacitly convert into a direct employment contract with the host organisation (inlener), even after a prolonged placement. Under the Working Hours Act and the Health and Safety at Work Act, however, the host organisation is treated as the employer of the seconded worker for the purposes of those specific statutes.