What must be signed by both the contractor and the contracting officer?

A bilateral modification is a type of contract modification that requires the agreement and signature of both parties involved in the contract: the contractor and the contracting officer. This ensures that any changes made to the original contract are mutually accepted, which is important for contract enforceability and maintaining a good working relationship between the contractor and the government.

In practice, bilateral modifications are utilized for various reasons, such as changes in the scope of work, adjustments in contract price, or other terms that affect both parties. When both the contractor and the contracting officer sign this modification, it reflects a joint agreement, which is critical in formalizing any amendments or adjustments to the original contract.

On the other hand, unilateral modifications can be made by one party (usually the contracting officer) without requiring the contractor's signature. While they may be used in certain circumstances, they do not have the same level of agreement and consent from both parties as bilateral modifications do.

Supplemental agreements typically refer to written agreements that add terms or clauses to the original contract, but this can include both unilateral and bilateral modifications, with the distinction that both parties may not need to agree on all supplemental agreements.

The Notice of Contract is a document that serves to officially inform involved parties of the award of a contract but does