An ex parte hearing or ex parte relief refers to a situation in which the judge only hears from one party to a dispute before making a decision on some limited issue being presented to the court. Because fairness and due process of law generally require both sides of a dispute to receive notice of a hearing and the opportunity to be heard at the hearing, there must be an emergency situation in which harm that cannot be undone (irreparable harm) will occur if the court does not act immediately—without giving the other party notice and the opportunity to be heard on the disputed issue.

Emergency matters that justify ex parte relief might include the theft of trade secrets by a former employee, or, in a child custody dispute, removing the child from the state, domestic violence, drug and alcohol abuse, sexual abuse of the child, and other situations that put the child in immediate danger.

In Arizona, an ex parte hearing or ex parte relief is a legal procedure where the court hears and decides on an urgent matter presented by one party without the presence or participation of the other party. This type of hearing is only granted under circumstances where there is a risk of irreparable harm that could occur if immediate action is not taken by the court. Arizona law recognizes the importance of due process, which typically includes notice to all parties and the opportunity to be heard. However, in emergency situations such as potential theft of trade secrets, immediate risks to a child's safety in custody disputes, domestic violence, or other scenarios where delay could result in significant harm, the court may issue orders on an ex parte basis. These orders are generally temporary and are subject to further review once the other party is notified and given the opportunity to respond.