Lead magnet / book choice
Red / Yellow / Silver — FIDIC book decision tree
A fast logic for book choice: who designs, how payment works, where risk sits and how much certainty the Employer needs.
Red / Yellow / Silver Decision Tree
A decision tree for choosing between FIDIC Red, Yellow and Silver Book by design responsibility, pricing and risk allocation.
- Employer design?
If the Employer designs and payment is by measurement, Red Book is the starting hypothesis.
- Contractor design?
If the Contractor designs and builds, Yellow Book usually needs checking.
- Turnkey certainty?
If high price/date certainty is required, test Silver Book.
- Site data quality
The weaker the data, the more dangerous aggressive risk transfer becomes.
- Particular Conditions
The final answer depends on changes in the Particular Conditions.
Why this exists
Choosing the book is the decision that costs more than any later Particular Conditions fix. It determines who designs, how work is valued, who carries ground risk and whether the project has an independent Engineer at all. The decision tree exists so that the choice follows the delivery model rather than whichever template the Employer’s lawyer happened to have.
Who it is for
- The Employer and its adviser — at project structuring stage, before the tender is prepared.
- The Contractor — to see whether the chosen form matches the real delivery model.
- Counsel — to see which Particular Conditions the chosen book will require.
How to run it on a project
- Start with design: who performs it and how developed it is at tender stage.
- Then settle the valuation method: re-measurement against a BoQ, or a lump sum with milestones.
- Test ground risk separately: where the geology is unexplored, the Silver Book is almost always the wrong answer.
- Cross-check against the Engineer’s role: if an independent contract administrator is needed, the Silver Book drops out.
Questions
What to choose when the design is only partly complete?
Mixed cases are not solved by picking a middle book but by drawing a clear line in the Employer’s Requirements: exactly what the Contractor designs and against which functional criteria it is accepted. The worst outcome is a Yellow Book whose requirements are half prescriptive solutions — responsibility for the outcome then blurs.
Why is the Silver Book a poor fit for MDB projects?
Development banks build procurement around transparent contract administration and an independent Engineer, while the Silver Book removes that role and shifts almost all risk to the Contractor. On publicly funded projects with mandatory reporting that model sits badly with the control requirements, which is why MDB tenders normally use the Pink Book or adapted Red and Yellow Books.