The FIDIC Red Book (edition 1999) deals with Value Engineering Clause.

Under FIDIC Red Book (1999), the Value Engineering Clause requires the Contractor to notify the Engineer with full details and cost implications when proposing Value Engineering changes. The Engineer then follows the Variation procedure in Sub-Clause 3.5 to agree or determine the cost adjustment, which will be reflected in the Contract Price.

This ensures transparent handling of Value Engineering proposals and proper contractual adjustments.