Interactive form selector

Choose the right FIDIC book

Answer a few practical questions: who designs, how the works are paid, how much price certainty is needed, whether MDB financing or geo-risk is involved. The result is a first orientation, not a substitute for reviewing the tender package.

Project type
Who should design
Pricing priority
Funding
Employer risk profile
Significant geo-risk / underground works

What this tool does

The tool matches answers about the delivery model against the profiles of the Rainbow Suite books and proposes the form that fits. The selection logic turns on three questions: who performs the design, how the work is valued, and who carries ground risk. Those three answers, rather than sector habit, determine the right book.

Where the inputs come from

  • Design — judge the actual state of the documentation at tender, not the plan to develop it further.
  • Valuation — whether there is a bill of quantities to measure against, or a lump sum against milestones.
  • Ground — whether the site has been investigated and the reports are in the tender package.
  • The Engineer’s role — whether an independent contract administrator is needed or the Employer will run it.

How to read the result

The result is a starting point for discussion, not a decision. If the tool suggests the Silver Book while the geology is unexplored, that is a signal about project readiness rather than about form selection. Mixed cases are not solved by a middle book but by drawing a clear line of responsibility in the Employer’s Requirements.

What this tool does not account for

  • Does not account for lender requirements: on MDB projects the form is often fixed by the bidding documents in advance.
  • Does not assess whether the local contractor market is ready for the chosen model.
  • Does not check the chosen form against local law — that is separate work on the Particular Conditions.
  • Does not distinguish variants within a book: the Red Book 2017 and the MDB Harmonised Edition behave differently.

Questions

What if the lender has already fixed the contract form?

Then the choice is closed, and the tool is useful differently — as a way to see where the imposed form diverges from the real delivery model. Each divergence will have to be closed in the Particular Conditions or priced in. That is precisely the list worth working through at tender clarification stage.

Can the Yellow Book be used when the design is half complete?

It can, but the danger lies elsewhere: the Employer’s Requirements are often half prescriptive solutions. The Contractor is then formally answerable for fitness for purpose while not controlling the key design decisions. If you go this way, draw the line explicitly in the requirements: what the Contractor designs and against which functional criteria it is accepted.