Since 2017, you may not work for the same company (hirer) for more than 18 consecutive months in a temporary employment agency. At least 3 months must then elapse before the respective temporary worker is re-employed at the same workplace. After these 3 months, the 18-month period begins again.
However, longer deployment periods can also be regulated in collective agreements or works agreements. It is also possible to override these deadlines by regularly rotating temporary workers. At least 3 months must elapse between assignments of the respective temporary worker at the same workplace.