What primary contractual mechanism defines who bears the majority of cost risk for unforeseen circumstances in a lump-sum contract?

The primary contractual mechanism that defines who bears the majority of cost risk for unforeseen circumstances in a lump-sum contract is the fixed price nature of the agreement itself. A lump-sum contract, also known as a fixed-price contract, is an agreement where the contractor commits to completing a specific scope of work for a single, predetermined, and unchangeable total price. This price remains constant regardless of the contractor's actual costs incurred to perform the work. Cost risk refers to the potential for the act....