The doctrine of unjust enrichment applies the principles of restitution to disputes that are not governed by a contract between the parties. It characterizes the result of a failure to make restitution under circumstances that give rise to an implied or quasi-contractual obligation to return those benefits.

The courts describe this claim in general principles. For example, courts have stated that a claim for unjust enrichment seeks to restore money where equity and good conscience require restitution; it is not premised on wrongdoing, but seeks to determine to which party, in equity, justice, and law, the money belongs; and it seeks to prevent unconscionable loss to the payor and unjust enrichment to the payee.

Because recovery based on unjust enrichment of another party relies on the court's sense of fairness or equity rather than the law, it is often referred to as the equitable doctrine of unjust enrichment.

In Louisiana, the doctrine of unjust enrichment is recognized and is referred to as 'enrichment without cause.' This doctrine is rooted in the civil law tradition and is codified in the Louisiana Civil Code. According to Louisiana law, a person who has been enriched without cause at the expense of another person is bound to compensate the latter to the extent of the enrichment, provided that the person who suffered the loss did not voluntarily consent to the enrichment. The claim for unjust enrichment in Louisiana is a last resort and can only be invoked when there is no other remedy available in law or contract. The courts in Louisiana will consider claims of unjust enrichment to prevent one party from being unjustly enriched at the expense of another, ensuring that restitution is made in situations where equity and good conscience dictate. However, the claimant must demonstrate that they have suffered a loss, that the other party has been enriched, that there is a connection between the enrichment and the loss, and that there is no justification or remedy provided by law for the enrichment and loss.