Benegal Narsing Rau was appointed as the advisor to the Constituent Assembly. He played a crucial role in framing the general structure of the Constitution and preparation of the first draft. He travelled to different countries and had extensive meetings with eminent jurists and political experts throughout the world. He was appointed as India's representative to the United Nations Security Council from 1950 to 1952. From February 1952 until his death, he was a judge of the International Court of Justice at The Hague.