The Spanish legal sources attended the institution of arbitration from long time ago. Arbitraje, avenencia, conciliación are terms with a special meaning on the different legal systems in Spanish History of Law. The law being in force in the Andalusi Community focused the attention of the jurist on the arbitraje because of two reasons. The first reason of this interest was due for being an effective and quick way to settle differences or disputes between parties. The second reason was due to the special features that this method of resolution presented regarding to the Maleki's orthodoxy. This paper analyzes the elements and features of arbitraje,and conciliacidn in order to draw a whole vision of the institution, since the Middle Ages, the period in which the institution was a useful resort to resolve controversial situations among Christians and Muslims.