Agency work puts three parties in a relationship built for two

One job, two contracts, and nobody obviously in charge

A temporary worker takes instructions from a manager at the site where they work, is paid by an agency they may never visit, and has a contract with the agency alone. The client has a contract with the agency too. What the client does not usually have is any contract with the person actually doing the work, which is where the difficulty starts.

Employment law was built around a two-party relationship in which the person giving instructions is the person owing the obligations. Splitting those functions between two businesses does not fit the model, and most systems have responded with a patchwork: some rights attach to the agency, some to the client, and some depend on how the arrangement actually operates rather than on how it is papered.

Who the employer is can be genuinely unclear

Different systems answer this differently. Some treat the agency as employer for most purposes; some look at who exercises day-to-day control; some recognise a contract between worker and client arising by implication where the arrangement has run long enough and the paperwork no longer reflects reality. Others treat agency workers as a distinct category with tailored rights and avoid the question.

The uncertainty is not academic. Which party is the employer determines who must handle a dismissal, who owes obligations about pay, and who a claim should be brought against. Bringing it against the wrong party can waste a limitation period, which is a harsh consequence for a confusion the worker did not create. It is one of the strongest reasons to take advice before issuing anything.

Equal treatment provisions are common but conditional

A number of jurisdictions require that agency workers receive treatment comparable to directly employed staff doing the same work, at least in respect of basic conditions, sometimes after a qualifying period. The reasoning is to prevent agency supply from being used as a permanent route around the terms that apply to everybody else.

These provisions are usually narrower than they first appear. They may cover only certain categories of term, may exclude occupational benefits, and may be subject to exceptions where the worker is employed permanently by the agency on particular arrangements. The comparison also requires a comparable direct employee to exist, which is not always the case. Whether such a regime applies where you are is a specific local question with a materially different answer from country to country.

Safety and site duties usually fall on the client

One thing tends to be clearer. The business where the work is done generally owes duties about the safety of the workplace to everybody working there, regardless of who employs them, because the occupier controls the premises and the activity. Induction, equipment, supervision and risk assessment are practical obligations that cannot sensibly sit with a distant agency.

Agencies commonly retain duties of their own — checking that the placement is suitable, that the worker has the qualifications claimed, and that the client has explained the risks. Where an agency worker is injured, the analysis often involves both businesses, and the allocation between them is exactly the sort of question that needs local expertise rather than assumption.

Gaps, continuity and the assignment that simply stops

Agency arrangements are frequently structured so that each assignment is discrete and there is no obligation on either side between placements. That structure has consequences: rights depending on continuous service may never accrue, and an assignment ending is often not a dismissal in any legal sense, merely a placement concluding.

It is also why long-running placements attract scrutiny. Where someone has worked at the same client for years, integrated into teams, managed like an employee and treated as part of the organisation, several systems will look at whether the reality has outgrown the paperwork. That is a fact-heavy assessment and it produces genuinely unpredictable results, which is a reason to get an opinion rather than to rely on either party’s confident assertion.

Ask who owes what before anything goes wrong

The classification of agency workers, the existence and scope of equal treatment rules, how safety duties are allocated and which party may be pursued differ substantially between jurisdictions, and several are actively legislating in this area. Nothing here is advice about a particular placement, and any real answer turns on how the arrangement actually works.

Two practical cautions. Keep your own record of who instructed you, where you worked and what you were paid, since agency records can be difficult to obtain later. And treat the deadline question as urgent: employment claims often carry short limitation periods, complaining to an agency or a client does not usually pause them, and uncertainty about which party to name is not generally an excuse for missing one. A qualified employment lawyer or a local advice service can answer both questions quickly.