An emergency injunction is a temporary directive from a court ordering someone to cease or continue a specific behavior, depending on the nature of the case. Emergency injunctions are used in cases where people can demonstrate that an injunction is needed to prevent serious harm or damages beyond financial damages in the immediate future. The person who initially requested it will need to provide supporting evidence to get a permanent injunction. It can be a stopgap measure to address an immediate situation while preparing for more long-term legal action.

Emergency injunctions can be used in a wide variety of settings including abuse cases, patent infringement cases, and child custody cases. To grant an emergency injunction, a judge must be shown that serious harm will occur unless the injunction is put in place. For example, in a divorce involving abuse, the abused partner might request an emergency injunction to order the other partner to stay away, on the grounds of personal safety concerns. If the abused partner has documentation like a history of police calls to the residence to address domestic violence complaints, the judge can grant the injunction.

Under normal circumstances, judges like to hear from all parties before granting an injunction, to make sure that people do not abuse the legal system. A company disliking the actions of a competitor, for instance, can't file an injunction randomly to stop the competitor from doing something. If a company can argue that a competitor is infringing on patents or committing other wrongs, it can bring suit to request a permanent injunction and recover damages. It may use a request for an emergency injunction to stop the competitor during the course of developing the trial and hearing it in court if it can show how the competitor's actions are causing direct harms like loss of reputation due to counterfeit products.

In an emergency injunction, the judge clearly outlines the activity covered by the injunction and sets well-defined boundaries on the scope of activity. Judges balance the needs of avoiding unreasonable restriction of liberty with addressing the concerns outlined in the injunction request. These documents are sometimes used as evidence in cases, and for this reason, judges are careful to outline the arguments presented during the injunction hearing.

Typically, emergency injunctions expire within a set period of time. People can apply to renew them or allow them to lapse. If a legal matter is decided before the injunction expires, the outcome of the case can result in a lift of the injunction, or the drafting of a permanent injunction.