The construction industry in Egypt frequently employs the standard conditions of contract published by the Fédération Internationale des Ingénieurs-Conseils (FIDIC), grounded in common law principles. However, the governing legal framework in Egypt is the Egyptian Civil Code (ECC), which draws its roots from French civil law and Shari'a law. This incon-gruence raises questions about the compatibility and interpretation of FIDIC provisions with-in the Egyptian legal context. This paper uses the doctrinal research method to examine the FIDIC Conditions of Contract for Construction (commonly known as FIDIC (CONS)) in the context of the ECC, with a particular focus on Article 657, which deals with managing risks related to quantity variations. The analysis highlights similarities and differences between FIDIC (CONS) and the ECC, especially in their approach to managing risks related to un-foreseeable physical conditions and design errors. The paper concludes that Article 657 of the ECC does not deviate from the principles of a unit price contract, as it does not apply to quantity increases caused by an inaccurate bill of quantities but is applicable in cases of un-foreseen occurrences. However, the ECC is observed to be less accommodating toward con tractors in the event of unforeseen occurrences.