Many contracts include an arbitration clause naming the AAA as the organization that will administer an arbitration between the parties. The AAA does not itself arbitrate disputes, but provides administrative support to arbitrations before a single arbitrator or a panel of three arbitrators. The arbitrators are chosen in accordance with the parties' agreement or, if the parties do not agree otherwise, in accordance with the AAA rules. Under its rules, the AAA may appoint an arbitrator in some circumstances, for example, where the parties cannot agree on an arbitrator or a party fails to exercise its right to appoint an arbitrator. Parties choose arbitration for a variety of reasons, including the perception that it is less costly and protracted than litigation in court.