The Arbeitnehmerüberlassungsgesetz (AÜG), or Temporary Agency Work Act, is the German statute that regulates the commercial hiring-out of workers (Leiharbeitnehmer) from a licensed agency (Verleiher) to a user undertaking (Entleiher). Any organisation commercially supplying temporary workers in Germany must hold a valid Erlaubnis zur Arbeitnehmerüberlassung (agency licence) issued by the Bundesagentur für Arbeit. Operating without a licence renders the supply contract void and triggers a deemed employment relationship between the worker and the user undertaking.
Under reforms effective since 2017, temporary workers are entitled to equal pay and working conditions matching those of the user undertaking's permanent workforce after nine months of continuous assignment, unless a collective agreement provides alternative arrangements. The maximum duration of any single assignment to one user undertaking is 18 months; a break of at least three months and one day is required before the same worker may be re-assigned to the same user in the same role. Betriebsrat consultation rights extend to temporary worker placements.
The AÜG also distinguishes lawful Arbeitnehmerüberlassung from unlawful Arbeitnehmerüberlassung or disguised Werkverträge (contract-work arrangements). Regulators and courts scrutinise the degree of integration and operational control exercised by the user undertaking. Organisations relying on contractors or seconded staff in Germany should conduct periodic AÜG compliance reviews to confirm that working arrangements do not inadvertently create liability under the statute.