Is it absolutely necessary that all business contracts be in writing? Can some things be done in a verbal contract?
Certain agreements MUST be in writing, in order to satisfy the Statute of Frauds. Other agreements do not NEED to be in writing. But in most cases, it is advisable. This is not your grandfather's business world, where people were as good as their word, and where a handshake was respected and sufficient. In this day and time, commerce has become much more complicated, and less concern is given to honesty and decency, and more concern is given to profit. This is not a positive change, but it is reality.
In situations where reasonable minds can differ as to what the agreement was, having the principal terms in writing just makes good sense. If there is ever a disagreement and it winds up in court, it is a lot easier to protect your interests by relying on a written document than on trying to piece together the terms by the subjective testimony of opposing sides.
It probably goes without saying, but most contracts are best left to the attorneys to draft.
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It is always a good idea, particularly in the case of business contracts, to have something in writing so as not to depend on "he said, she said."
That being said, the requirements for a contract/obligation in Louisiana do not, by default, require something in writing.
"A contract is an agreement between 2+ persons by which obligations are created, modified or extinguished.
Four elements of a valid contract: capacity, consent, lawful cause, and lawful object."
The answer given here should be considered general in nature and should not be considered legal advice, or that there has been an attorney-client relationship established. It is always suggested to retain the counsel of a lawyer for legal advice specific to your situation.