FIDIC Contracts Explained: Red, Yellow and Silver Books (2026)

What are the FIDIC Red, Yellow and Silver Books? FIDIC is the International Federation of Consulting Engineers. It publishes standard forms of construction and engineering contract used on projects around the world, often on cross-border and infrastructure work. The three best known forms are known by their cover colours. The main thing that separates them is a single question: who prepares the design, and who carries the risk if things go wrong. In short: - Red Book (Conditions of Contract for Construction): the employer provides the design, and the contractor builds to it. Payment is usually re-measured against actual quantities.

• Yellow Book (Conditions of Contract for Plant and Design-Build): the contractor designs and builds to meet the employer's requirements. Payment is usually a lump sum.
• Silver Book (Conditions of Contract for EPC / Turnkey Projects): the contractor takes on the most risk, delivers a complete, ready-to-run facility, and gives the employer a high degree of price and time certainty. The current main editions were published in 2017 (a second edition of the 1999 forms), and this group is often called the "rainbow suite". This is general guidance, not legal advice, and particular conditions on a real project can change any of the points below. ## The core difference: design and risk | Feature | Red Book | Yellow Book | Silver Book | |---|---|---|---| | Who designs | Employer | Contractor | Contractor | | Design basis | Drawings and specifications | Employer's Requirements | Employer's Requirements | | Typical pricing | Re-measurement (bill of quantities) | Lump sum | Lump sum | | Risk on employer | Higher | Moderate | Lower | | Risk on contractor | Lower | Moderate | Higher | | Price and time certainty for employer | Lower | Moderate | Higher | | Best suited to | Employer-designed building and civil works | Plant and design-build works | Turnkey, process and privately financed projects | ### Red Book: employer designs, contractor builds Under the Red Book the employer (through its engineer) prepares the design and issues drawings and specifications. The contractor builds what it is given. Because quantities are rarely exact at tender, payment is normally based on re-measurement against a bill of quantities. If the design is wrong, that is usually the employer's problem, and the contractor claims for the extra work as a variation. The Red Book suits traditional building and civil engineering where the employer wants to control the design. ### Yellow Book: contractor designs and builds The Yellow Book is a design-build form. The employer sets out what it needs in a document called the Employer's Requirements, and the contractor designs and builds to meet them, usually for a lump sum. If the contractor finds a genuine error in the Employer's Requirements, that is generally dealt with as a variation, which can mean more time and money for the contractor. The Yellow Book suits plant, electrical and mechanical works, and projects where the employer wants the contractor to own the design. ### Silver Book: turnkey, maximum certainty, maximum risk transfer The Silver Book is an EPC (engineer, procure, construct) or turnkey form. The contractor takes near-total responsibility: it designs, procures and builds a complete facility for a fixed price and a fixed date, and hands over a working plant. The trade-off is a high degree of risk transfer to the contractor, including, in many cases, responsibility for errors in the Employer's Requirements and for site and ground conditions. Because of that, commentators warn that the Silver Book should be used in defined situations, often where price and time certainty matter most, such as privately financed or lender-driven projects. It is not a drop-in replacement for the other books, and analysing a Silver Book dispute with Red Book assumptions can lead to the wrong answer on who owns a risk. ## The role of the Engineer (and why the Silver Book is different) The Red and Yellow Books use an "Engineer", a third party appointed by the employer who administers the contract, certifies payment and is expected to act fairly when making determinations between the parties. The Silver Book usually has no independent Engineer; the employer administers the contract itself (often through an Employer's Representative). That is another reason the Silver Book sits apart from the other two. ## How to choose the right book Ask these questions before picking a form: 1. Who should own the design? Employer design points to the Red Book. Contractor design points to the Yellow or Silver Book.

2. How much price and time certainty do you need? If certainty is critical, for example because lenders require it, the Silver Book leans that way, at the cost of a higher contract price to reflect the risk the contractor is pricing in.
3. How well defined is the scope at tender? A well defined, stable scope supports a lump sum (Yellow or Silver). A scope likely to change supports re-measurement (Red).
4. Who is best placed to carry ground and site risk? The Silver Book tends to push this onto the contractor; the other forms share it more.
5. Do you need an independent certifier? If yes, the Red or Yellow Book and their Engineer role fit better. ## Other books in the suite The rainbow suite is wider than three colours. There is also the Green Book (a short form for small or simple works), the Gold Book (design-build-operate), the Emerald Book (underground works), and forms for dredging, subconsultancy and client-consultant services. The Red, Yellow and Silver Books are simply the ones most people mean when they say "a FIDIC contract". ## A note on jurisdiction FIDIC forms are templates, not law. They are written to work across borders, but the governing law chosen in the contract, and any mandatory local rules, will override or reshape parts of them. In India, for example, FIDIC forms are widely used on infrastructure work but are read alongside the Indian Contract Act, 1872, the Arbitration and Conciliation Act, 1996, and public-procurement conditions, and employers often add particular conditions that change the standard risk allocation. Always read the particular conditions, not just the general conditions, because that is where the real deal usually lives. ## Where a contract workspace helps A FIDIC project lives or dies on detail: the right book, the particular conditions that amend it, the Employer's Requirements, the variations, the claims and the deadlines for notices. Much of the pain on these projects comes from scattered versions, missed notice periods and risk that is buried in clauses nobody reread. That is the idea behind a single AI contract workspace. It can model a contract as a structured clause tree rather than flat text, so each clause and its risk can be seen in one place, flag positions that are favourable, neutral or unfavourable to your side, let you edit terms in plain language, and keep key dates and obligations visible on a live timeline. Tools such as Adira are built around that one-workspace idea. Choosing and understanding the right FIDIC book is work this article alone can help you do; a workspace simply keeps the drafting, the review and the deadlines connected instead of spread across inboxes and folders.