If you’re evaluating an engineering partner for a project in Italy — a renewable energy plant, an infrastructure scheme, an industrial facility — most of what’s available online is written for professionals who want to set up an engineering company, not for clients who need to assess one before signing a contract. Italian legal forms, insurance requirements, and procurement rules aren’t always intuitive from outside the country, and getting them wrong can cost you months once a project is underway.
This guide is for project managers, technical directors, contracting authorities, and private clients who need to appoint a structured engineering partner for design, site supervision, or construction management in Italy — and want objective criteria to do it well.
Why choosing an engineering partner goes beyond the project portfolio
A strong portfolio is a starting point, not a conclusion. It shows the company has delivered projects similar to yours — but it says nothing about how the organisation is structured, who is civilly liable if something goes wrong with the design, or whether the company genuinely has the in-house capacity to cover every discipline your project needs.
The difference between a good and a bad choice usually becomes visible months after signing: when a design discrepancy surfaces on site, when a permit wasn’t filed on time, or when the technical team changes mid-project without anyone telling you.
Three fundamental questions that clients rarely ask — but should.
Who is civilly liable if the design has errors? The answer depends on the company’s legal form. An associated practice, a professional services company (STP), and a traditional engineering company are not equivalent from a liability standpoint.
Does the structure guarantee operational continuity over time? Complex projects run for years. The ability to guarantee continuity through a documented organisational chart is a concrete safeguard, not just a commercial nicety.
Does the partner have the regulatory expertise your context requires? A public sector client has very different needs from a private one. Familiarity with the procurement framework — and its practical implications on site — isn’t optional.
Engineering company, associated practice, and STP: the differences that matter to clients
The Italian engineering services market is organised around three main legal forms: the associated professional practice, the professional services company (STP — Società tra Professionisti), and the traditional engineering company. Understanding the differences from a client’s perspective is the first step to choosing with confidence.
Associated practices and their operational limits
The associated practice (studio associato) is the most common form in the Italian professional landscape. The partners are personally and jointly liable for obligations arising from their professional activity. That can work for small, well-defined assignments, but it becomes a structural limitation for multi-year, large-scale contracts: an associated practice has no separate legal personality, holds no corporate assets distinct from its partners’, and if a partner leaves, the disruption falls directly on the project in progress.
For clients appointing long-term partners on complex projects — energy facilities, infrastructure, large-scale construction — this fragility is a real risk to factor in before signing.
Professional services companies (STP) and Benefit Company status
The Professional Services Company (STP), introduced by Italian Law No. 183/2011 and regulated by Ministerial Decree No. 34/2013, allows professionals — engineers and architects — to practise through a company with its own legal personality. The law requires registered professionals to hold at least two-thirds of the share capital and voting rights: a guarantee that governance stays in the hands of those who carry technical and professional liability.
One detail clients often overlook: an STP is legally required to hold professional indemnity (PI) insurance. This isn’t a matter of good practice — it’s a statutory requirement. As a client, you have both the right and the interest to request a copy of the policy before signing any agreement, and to check its coverage limits against the type of project involved.
When an STP also holds Benefit Company status — as is the case for SetinStudio, which became an S.r.l. STP SB (Benefit Company) in January 2026 — there’s an additional layer of transparency: the company is bound by its bylaws to pursue defined public-benefit purposes alongside profit, with verifiable annual reporting. This isn’t just a values statement — it’s a signal of organisational solidity and a long-term orientation.
Procurement compliance: how to assess a partner’s regulatory expertise
For a public sector client, choosing an engineering company also means choosing a partner that understands the procurement framework from the inside. Site supervision without a solid grasp of the Italian Public Contracts Code (Legislative Decree 36/2023) exposes a project to design variations during construction, disputes with contractors, and permitting delays that, on large contracts, translate into penalties and lost funding.
Clarifying a common misunderstanding: design qualifications vs. SOA certification
It’s a more common mistake than you’d think: some clients ask an engineering company for SOA certification as proof of qualification. This reflects a structural misunderstanding of how the Italian construction market is organised.
SOA certification is the mandatory qualification system for public works contractors — the builders, not the designers. An engineering company doesn’t need, and shouldn’t be expected to hold, an SOA certificate to provide professional design services: the qualification requirements for design firms are set out in Article 66 and Annex II.12 of Legislative Decree 36/2023, and cover registration of the signing professionals, organisational structure, and PI insurance.
Knowing this distinction — and being able to explain it precisely when the confusion comes up — is a direct indicator of a partner’s regulatory competence. A company that operates confidently on both sides of the market (design and construction) can draft tender documents and detailed designs that anticipate problems instead of creating them.
The Italian Public Contracts Code (Legislative Decree 36/2023) and managing design variations
Legislative Decree 36/2023 significantly updated the regulatory framework compared with the previous Decree 50/2016. Article 66 and Annex II.12 set out the requirements for parties appointed to provide architectural and engineering services: one of the most significant changes is the requirement that A&E activity be explicitly stated in the appointed party’s corporate purpose.
For public sector clients, this translates into more precise verification obligations during tender procedures. For private clients not bound by the Code’s procedures, knowing that a partner meets the requirements for public contracts is still a useful signal of solid, verifiable organisational structure.
Managing design variations during construction is the other area where regulatory competence makes a practical difference. A well-developed detailed design significantly reduces the likelihood of variations. When a variation is unavoidable — unforeseen site conditions, client-requested changes, clashes with existing utilities — the engineering company needs to manage the procedural process without stopping the works. This is part of our approach to project delivery: managing critical phases is part of the service, not an add-on.
3 critical mistakes to avoid when selecting a B2B engineering partner
Working across more than 100 concurrent assignments has let us observe recurring patterns in how clients get partner selection wrong. The most expensive mistakes are almost always avoidable.
- Mistake 1 — Choosing on price without checking qualifications. A low bid from a firm with no track record in your project’s sector isn’t a saving — it’s a deferred risk. The cost of a flawed design — in variations, delays, and disputes — consistently outweighs whatever was saved at the appointment stage. Price should be the last criterion you weigh, not the first.
- Mistake 2 — Asking a designer for SOA certification instead of a contractor. As explained above, SOA certification applies to public works contractors, not professional engineering companies. Confusing the two qualification systems leads either to excluding qualified professionals or to evaluating firms against the wrong requirements.
- Mistake 3 — Not checking PI insurance before signing. Insurance cover is a legal requirement for STPs, but in practice it’s often overlooked on private appointments. Coverage limits, exclusions, and validity periods are details to verify before signing. Always ask for a copy of the policy and confirm it covers the specific type of appointment.
Frequently asked questions about choosing an engineering company in Italy
What’s the practical difference between an engineering company and an STP?
From a client’s perspective, the main difference lies in governance. In an STP (Law 183/2011, Decree 34/2013), registered professionals must hold at least two-thirds of the capital and voting rights: strategic decisions stay with those who carry professional liability. In a non-STP engineering company, shareholders can include people without professional registration — including financial investors — without that constraint.
Who is civilly liable if the design has errors?
Liability sits on multiple levels: the signing professional is personally liable, and the company is liable through its PI insurance, which is mandatory for STPs. This layered liability structure is a concrete advantage over appointing a single professional directly.
What should I check before signing an appointment?
At minimum: professional registration of the named signing professionals; PI insurance (coverage limits, validity, and scope relative to the appointment); the project organisational chart with names and roles; references on projects of similar scope and complexity. For public tenders, ANAC (Italy’s National Anti-Corruption Authority) maintains a register of engineering companies.
Can a smaller firm bid for a public design contract?
Yes, provided it meets the requirements proportional to the contract value set out in Annex II.12 of Legislative Decree 36/2023. For large-scale contracts, temporary consortiums (RTI) allow multiple qualified parties to pool their requirements.
Is a written contract necessary for a private appointment?
It isn’t a legal requirement in every case, but it’s strongly recommended. A contract defining scope, phases, fees, liabilities, and delivery terms is the main protection for both parties. Without a written agreement, reconstructing obligations in the event of a dispute becomes far more difficult and costly for everyone involved.
From concept to operations: the value of a single technical partner
Appointing a partner who covers every phase of a project’s life cycle — from feasibility through detailed design, from site supervision to asset management — isn’t just an operational convenience. It reduces the number of interfaces, removes responsibility gaps between different parties, and preserves project knowledge over time.
At SetinStudio, this is how we work on every assignment: multidisciplinary teams with a single point of contact for the client, backed by specialised Business Units by sector — renewable energy, infrastructure, environment, and construction. It’s the model that lets us manage over 100 concurrent assignments, with national and international clients including Vestas, Repsol, Nordex, and A2A. You can find out more about our teams and Business Units on our company page.
If you’re evaluating a partner for your next project — a renewable energy facility, an infrastructure scheme, environmental remediation, or a complex construction programme — we’re available to discuss the specifics of your context. You can explore our services in detail or get in touch directly: an engineer always answers.
