Which of these is NOT a requirement for a contract to be valid?

A valid contract requires several essential elements to be enforceable, and among these, written documentation is not always a strict requirement. While having a written contract can help to clarify the terms and protect the parties involved, many agreements can be legally valid and enforceable even if they are not documented in writing, especially for less complex transactions.

The critical components of a valid contract include consideration, which refers to something of value being exchanged between the parties; a legal purpose, meaning the contract must not involve illegal activities; and competent parties, ensuring that those entering the contract have the legal capacity to do so, such as being of legal age and mentally sound.

Thus, while it is advisable to have a written contract to avoid misunderstandings and provide clarity, the absence of a written document does not inherently invalidate a contract as long as the other essential elements are present.