Who Does What on a French Building Project?
You've decided to build or renovate in France. Congratulations. You now have to deal with a cast of characters whose job titles are all abbreviations, whose roles overlap in ways nobody explains, and whose relationships to each other (and to you) determine whether your project runs smoothly or turns into a slow-motion administrative disaster.
Here's who they are, what they actually do, and why it matters.
MOA: Maître d'Ouvrage (That's You)
The maître d'ouvrage is the client. The project owner. The person whose money is on the line and whose name goes on the permis de construire.
In plain terms: you.
The MOA defines what they want, approves the budget, signs the contracts, and ultimately carries responsibility for the project. You don't need to know how to read a structural drawing. That's what you're paying everyone else for. But you do need to make decisions and stick to them. Changing your mind at APD stage costs money. Changing your mind during works costs much more.
The one thing most MOAs underestimate: your job isn't just to write cheques. You're the decision-maker at every stage. Show up, engage, and ask questions when something doesn't look right. The professionals on your team are there to advise you. The final call is always yours.
AMO: Assistant à Maître d'Ouvrage
The MOA's right hand. Sometimes.
An AMO is brought in when the client needs help managing the project itself. Not designing it, but overseeing it. They can handle programming (translating your needs into a brief the design team can work from), contract management, coordination between consultants, and specialist expertise in areas like BIM, environmental performance, or asbestos.
On smaller residential projects, an AMO is rare. On larger operations (public buildings, complex renovations, anything with multiple stakeholders) they're invaluable. They're essentially a project manager working on your side of the table.
If your architect is telling you what you need, an AMO is the person who helps you verify that independently.
MOE: Maître d'Oeuvre (The Design Team)
The maître d'oeuvre is the design and supervision team. On most projects, that means the architect. But on anything beyond a straightforward house, the MOE is a whole ensemble.
The agence d'architecture leads the design, from the first sketch to the final permit drawings. They're responsible for the project's architectural vision and the technical coordination of everyone else.
Around them sit the bureaux d'études, specialist engineers covering structural calculations, electrical design, HVAC and CVC systems, thermal performance, and increasingly, BIM coordination. You rarely deal with them directly. The architect does.
Other specialists join depending on the project: acousticians, asbestos management consultants (MOE Amiante), materials reuse experts (réemploi). French construction has a lot of specialists. That's not a complaint. It's just the reality of a sector that takes technical compliance seriously.
One thing worth knowing: not every project goes through an architect. If you're building under a CCMI (Contrat de Construction de Maison Individuelle), the constructeur de maisons individuelles takes on the MOE role themselves. That changes the dynamic considerably. You have less direct visibility over the design process and less independent oversight. It's not necessarily worse, but it's different, and it's worth understanding before you sign anything.
Here's the thing people miss: the MOE works for you, not the other way round. They have professional obligations, insurance, and legal responsibilities. But their brief comes from you, via the programme. Get the brief right and the rest follows.
CT: Contrôleur Technique
The technical inspector. Independent. Not on your payroll in the usual sense, but you're paying for them.
The CT verifies that the project complies with structural, fire safety, and accessibility regulations. They review calculations, check technical documents, and issue opinions (avis) at each design phase. On projects above certain thresholds, their involvement is mandatory.
They will find things. That's their job. A good CT finding something at design stage is free. The same thing found on site during works is expensive. And found after completion is a problem with a capital P.
Don't treat the CT as an adversary. They're a second pair of technically qualified eyes on something you're about to spend a lot of money on.
CSPS: Coordinateur SPS (Sécurité et Protection de la Santé)
Health and safety coordinator. Required on any project involving more than one contractor.
The CSPS's job is to coordinate safety between the different trades on site, making sure that what the electrician is doing on Wednesday doesn't create a hazard for the plasterer arriving Thursday. They produce the Plan Général de Coordination (PGC) before works start and oversee it throughout.
Their role is often invisible when everything goes well. When it goes wrong, when there's an accident on site and the paperwork isn't in order, it becomes very visible, very quickly.
On most residential self-build projects with a single main contractor, a CSPS isn't required. The moment you have two separate contractors working simultaneously, the obligation kicks in.
Entreprises: The People Who Actually Build It
At the end of the chain: the contractors. The ones with the tools, the vans, the Friday afternoon "it'll be done Monday" energy.
The entreprises are selected through the DCE (Dossier de Consultation des Entreprises), the tender package prepared by the MOE. They bid on the work, the MOE analyses the offers (analyse des offres), and contracts (marchés de travaux) are signed.
A word from someone who's been on sites: the relationship between the MOE and the contractors during works is where projects live or die. The best design in the world doesn't survive a contractor who ignores the drawings. The VISA, DET, and AOR phases exist precisely to keep that relationship managed and documented.
Why This Matters to You
Understanding who does what isn't just organisational housekeeping. It's about knowing who to call when something isn't right, who has the authority to make a decision, and who's responsible if something goes wrong.
On a French building project, everyone has a defined role and a defined liability. The system is complex, but it's coherent. Once you understand the structure, navigating it gets a lot less intimidating.
French construction is complicated enough already. Having someone who understands both site reality and technical documentation helps.