Discovery is the factfinding process in civil litigation in which the parties to a lawsuit exchange requests for the production of documents and other tangible items (requests for production); written questions to be answered under oath (interrogatories); witness testimony to be provided by oral deposition; disclosures that may be required under the applicable rules without request from an opposing party; and requests or subpoenas to third-parties (who are not parties to the lawsuit) for the production of documents or tangible things, or the giving of testimony by oral deposition, for example.

The discovery process is one of the most important, time-consuming, and often expensive parts of civil litigation. The discovery process—including the scope of discovery requests, deadlines to respond, and privileges from responding—are usually governed by the state or jurisdiction’s rules of civil procedure or code of civil procedure. For example, in federal court discovery is governed by the Federal Rules of Civil Procedure.

In South Dakota, the discovery process in civil litigation is governed by the South Dakota Codified Laws and the South Dakota Rules of Civil Procedure. These rules outline the methods by which parties can obtain evidence from each other, including requests for production of documents, interrogatories, depositions, and required disclosures. The scope of discovery in South Dakota allows for the gathering of any non-privileged information that is relevant to any party's claim or defense and is proportional to the needs of the case. The rules also set forth the time frames for responding to discovery requests and the assertion of privileges to protect certain information from being disclosed. Discovery can be a complex and strategic part of the litigation process, often involving negotiations between parties to narrow issues and facilitate the efficient exchange of information. Attorneys play a crucial role in managing the discovery process, ensuring compliance with the rules, and protecting their clients' interests.