Collective agreements can only be made compulsory if the agreement itself already covers a clear majority of employers and workers in the sector.  It is interesting to note that the Minister will consider unsealed workers in calculating the volume of the original agreement. Although they are not strictly bound by the collective agreement, they are considered to be registered by the collective agreement. Because inter-professional agreements are almost automatically declared of general application, most workers are somehow tied to a collective agreement. It is therefore essential to examine in more detail the limitations of the collective agreement law and its relationship to the individual contract. The collective agreements of workers who are not members of a union that is a party to the collective agreement are so-called unsegerated or otherwise organized workers. However, under section 14 of the Collective Agreements Act, an employer bound by a collective agreement is required to apply the contract to its unsealed or otherwise organized workers.  Most employers would fulfill this obligation by agreeing with each of their employees that the current interprofessional agreement applies to their contract. In this way, up to 85% of workers are covered by a collective agreement, while only about 26% are affiliated with a union.  The influence of Dutch trade unions far exceeds their representativeness solely because of membership. The collective labour law (declaration of general commitment and non-binding status) only reinforces this effect. As a general rule, companies employ only the workers needed for their core activities.
Secondary functions such as cleaning and restoration could be tendered for specialized companies. Even in the core business, not all staff are employed by the company itself. First, the Netherlands has a high percentage of people working through temporary employment agencies. Second, professionals and skilled workers are gradually seeking to maintain or regain their independence. You work as independents without staff (zelfstandigen zonder personeel). These phenomena affect the structure of collective bargaining.