A nondisclosure agreement—also known as an NDA, a confidentiality agreement, or a confidential disclosure agreement (CDA)—is a legally enforceable contract between persons or entities who want to share confidential, proprietary information with each other without the other party or parties to the agreement (1) using the information shared for a purpose other than the intended purpose (as defined in the NDA) or (2) sharing the confidential, proprietary information with persons or entities who are not parties to the NDA.

Nondisclosure agreements are generally interpreted and enforced according to the contract law of the state where one or both parties are located, and may governed by the law of the state the parties’ agreed to in a choice of law provision in the NDA.

In South Dakota, nondisclosure agreements (NDAs) are recognized and enforceable contracts used to protect confidential and proprietary information from being disclosed or used for unauthorized purposes. These agreements are subject to South Dakota's contract laws, which require that the agreements be entered into voluntarily, with consideration, and by parties who have the capacity to contract. The enforceability of an NDA in South Dakota will depend on the agreement's clarity, the reasonableness of its terms, and its compliance with public policy. Additionally, the parties to an NDA can choose to include a 'choice of law' provision, specifying that the laws of a particular state will govern the interpretation and enforcement of the agreement. If a dispute arises regarding the NDA, South Dakota courts will evaluate the agreement based on the specified governing law, provided that the choice is reasonable and does not contravene a fundamental policy of the state. It is advisable for parties entering into an NDA to consult with an attorney to ensure that the agreement is legally sound and tailored to the specific circumstances of the disclosure.