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 Alabama, consolidation of lawsuits is governed by the Alabama 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. This means that if two or more lawsuits share the same legal issues or facts, they can be consolidated to avoid unnecessary costs or delay. The decision to consolidate is at the discretion of the court and is typically done to promote efficiency and judicial economy. If the lawsuits are in different courts within the state, a transfer may be necessary to consolidate them in one court. The process for transferring cases may involve a request to the court where one of the cases is pending to transfer the case to the other court for consolidation. In the federal court system, similar provisions for consolidation are found under Rule 42(a) of the Federal Rules of Civil Procedure. The federal courts also consider the convenience of parties and witnesses, as well as the interests of justice when deciding whether to consolidate cases.