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 Texas, the doctrine of unjust enrichment is recognized and applied by courts to prevent one party from unfairly benefiting at the expense of another in the absence of a formal contract. This doctrine is rooted in the principles of equity and restitution, and it allows a party to recover benefits that were unjustly retained by another party, creating an obligation similar to that which would arise from a contract (implied or quasi-contractual obligation). Texas courts will consider an unjust enrichment claim when one party has received a benefit that in fairness and good conscience should be paid for, but for which no contractual obligation exists. The key consideration is whether it would be inequitable for the party who received the benefit to retain it without compensating the provider. This remedy is not based on the presence of wrongful conduct but rather on the notion that it is unjust for a person to retain benefits at another's expense. It is important to note that unjust enrichment claims in Texas are subject to certain defenses and limitations, and the specifics of each case will determine the applicability and success of such a claim.