A writ of prohibition is a writ directing a subordinate to stop doing something the law prohibits. This writ is often issued by a superior court to the lower court directing it not to proceed with a case which does not fall under its jurisdiction.

Writs of prohibition can be subdivided into "alternative writs" and "peremptory writs". An alternative writ directs the recipient to immediately act, or desist, and "show cause" why the directive should not be made permanent. A peremptory writ directs the recipient to immediately act, or desist, and "return" the writ, with certification of its compliance, within a certain time.

When an agency of an official body is the target of the writ of prohibition, the writ is directed to the official body over which the court has direct jurisdiction, ordering the official body to cause the agency to desist.

Although the rest of this article speaks to judicial processes, a writ of prohibition may be directed by any court of record (i.e., higher than a misdemeanor court) toward any official body, whether a court or a county, city or town government, that is within the court's jurisdiction.