An employment contract exists if someone commits themselves to perform work for another person. It is mutually binding, as both contracting parties (employer & employee) have rights as well as duties. The employment/service contract governs the rights and duties of employers and employees, unless they have been laid down on a compulsory basis by law or in collective bargaining agreements. 

Employment/service contracts are subject to compulsory social insurance under the General Social Insurance Act (Allgemeines Sozialversicherungsgesetz, ASVG) if the monthly remuneration is higher than the applicable marginal earnings threshold.