Consolidation of lawsuits may be ordered by a court when two or more lawsuits involving the same or similar parties (plaintiff and defendant), legal issues, and factual issues are pending in the same court or in different courts in the same jurisdiction (state court system or federal court system). If the lawsuits are pending in different courts one case may be transferred to the other court, and the cases consolidated there.

Laws and rules regarding the consolidation—or transfer and consolidation—of lawsuits vary from state to state and in the federal court system.

In North Carolina, consolidation of lawsuits is governed by the North Carolina Rules of Civil Procedure, specifically Rule 42(a), which allows for consolidation when actions involving a common question of law or fact are pending before the court. The court may order a joint hearing or trial of any or all the matters in question in the actions, or it may order the actions consolidated, and it may make such orders concerning proceedings therein as may tend to avoid unnecessary costs or delay. This is applicable when the cases are in the same court or in different courts within the state court system. If the lawsuits are pending in different jurisdictions, such as one in state court and one in federal court, the process becomes more complex and typically requires coordination between the two court systems. Federal courts have their own rules for consolidation under Federal Rule of Civil Procedure 42(a). The decision to consolidate is at the discretion of the court and is intended to promote efficiency and reduce the burden on the parties and the court system by avoiding duplicate efforts and inconsistent rulings.