The hallmark of international commercial arbitration is the right of parties to select the law to govern their dispute. However, choice of law or party autonomy is subject to limits. Sometimes arbitrators are obliged to aplly the mandatory law of a jurisdiction contrary to the will of one or more of the parties. The scope of these issues was discussed by Igor Ellyn in a presentation to the NY State Bar Association and Cornell University at the Bloomberg Center in New York in March 2008. These power point slides summarize the presentation.