Alternative dispute resolution or ADR is a name for several dispute resolution processes and techniques which, while believed by some to be outside the traditional mainstream of state jurisprudence, have gained acceptance among both the general public and the legal profession. In this terminology the processes were initially termed "alternative" by twentieth century legal typologists because they were seen as extra-legal supplements to state-sponsored dispute resolution. With the continuing increase in caseload placing great strain on traditional courts, many judges have come to see dispute resolution as an acceptable means of decreasing caseload in traditional courts, while settling disputes in a fair and equitable way. While some would not agree that all alternative methods are always fair and equitable, such methods are much less expensive than a traditional lawsuit.

Arbitration was actually one of the earliest forms of dispute resolution. It was practiced by the jurisconsults of the Roman Empire, and predates the adversarial system of the common law by at least a thousand years. Many people have played the role of mediator, conciliator or arbitrator in many jurisdictions at many times. The Vodun priests of Haiti are well known for their dispute resolution role which occasionally resulted in the losing party being forced to become a zombie. The King of France refused lawyers permission to practice in New France, so Catholic priests and civil law notaries were used by the local populace as dispute resolution resources.

See also arbitration, mediation, conciliation, and negotiation.