In my opinion, it depends on the "Unitarial theory" (Bipartism) that most developing countries are now adopting in the workplace. Union density is declining or not practicable at all because the belief is that they may compromise the strategic plans of the organization. Additionally, most of the employed individuals recruited are professionals and qualified personnel.
In some situations, some international corporate entities investing in underdeveloped or developing countries bring with them these ideologies, which may hinder the local labor laws of the host country. However, in some countries, mostly in the Commonwealth, they have strong labor laws that protect the interests of employees. It is the right of the employee to join the union, which the law deems supreme. However, in developing countries like the USA, some parts of the UK like Germany, Austria, and Australia, labor laws or union affiliations are reduced. Hence, there is no need to join a union because the work pattern in those countries differs, such as part-time, casual, or flexible work. Additionally, in some instances, the country has overqualified personnel that flood the market and increase economic status, speaking for itself.
If your country has strong labor laws that protect the interests of the employee and the right for union membership, then the contract will be contradictory and misleading to cite in the appointment letter (Corporatism theory) or (Tripartism).
Regards,
Pita Tuiloma
Fiji