At first sight, the answer to this question would be: only by mutual agreement. But once you take a closer look there are many ways and situations that make it possible for an employer to unilaterally change the contractual terms.
- Collective bargaining agreements (CBAs) are binding for members of those employers’ associations (firms) and labour unions (employees) who have concluded the respective agreements. In such case, any existing or newly concluded CBA will constitute new rules and obligations for the employee unless expressly stated otherwise in the employment contract. Since employers who are members of the employers’ associations do not