Rule of law is the supreme manifestation of human civilization and culture and is a new 'lingua franca' of global moral thought. It is an eternal value of constitutionalism and inherent attribute of democracy and good governance. The term 'Rule of law' is derived from the French phrase 'la principe de legalite' which means the 'principal of legality'. It refers to 'a government based on principles of law and not of men'. In other words, the concept of 'la Principe de legalite' is opposed to arbitrary powers. It is a legal principle, of general application, which is sanctioned by the recognition of authorities, and usually expressed in the form of a maxim or logical proposition called a 'Rule,' because in doubtful or unforeseen cases it is a guide or norm for their decision. The Rule of law, sometimes called 'the supremacy of law', provides that decisions should be made by the application of known principles or laws without the intervention of discretion in their application. The concept of Rule of law is of old origin. It is an ancient ideal, and was discussed by Ancient Greek philosophers such as Plato and Aristotle around 350 BC. Plato wrote: 'Where the law is subject to some other authority and has none of its own, the collapse of the state, in my view, is not far off; but if law is the master of the government and the government is its slave, then the situation is full of promise and men enjoy all the blessings that the gods shower on a state.' Likewise, Aristotle also endorsed the concept of Rule of law by writing that 'law should govern and those in power should be servants of the laws.' In UK, Sir Edward coke is said to be the originator of this concept, when he said that the king must be under the god and law and thus vindicated the supremacy of law over the pretensions of the executives. Later, Prof. Albert Venn Dicey developed this concept. He was an individualist. He wrote about the concept of rule of law at the end of the golden Victorian era of laissez faire in England. That was the reason why Dicey’s concept of the rule of law contemplated the absence of wide powers in the hands of governmental officials. According to him, wherever there is discretion, there is room for arbitrariness. In India, the concept of Rule of law can be traced to Upanishad. It provides that the law is the king of kings. It is more powerful and rigid than the kings. There is nothing higher than law. By its powers the weak shall prevail over the strong and justice shall triumph. Thus, in monarchy, the concept of law developed to control the exercise of arbitrary powers of the monarchs who claimed divine powers to rule. In democracy, the concept has assumed different dimension and means that the holders of public powers must be able to justify publicly that the exercise of power is legally valid and socially just. The Rule of law is viable and dynamic concept and like many other concepts, is not capable of any exact definition. This, however, does not mean that there is no agreement on the basic values which it represents. The term of Rule of law is used in contradistinction to rule of man and rule according to law. Even in the most autocratic forms of government there is some law according to which the powers of the government are exercised but it does not mean that there is Rule of law. Therefore, the Rule of law means that the law rules, which is based on the principles of freedom, equality, non-discrimination, fraternity, accountability and non arbitrariness and is certain, regular and predictable, using the word law in the sense of 'Jus' and 'lex' both. In this sense, rule of law is an ideal. It is modern name for Natural law. In ancient times, man has always appealed to something higher than which is his own creation. In Jurisprudence, Romans called it 'jus naturale' Mediaevalists called it the 'law of god'. Hobbes, Locke, Rousseau called it a ‘social contract' or natural law and the modern man calls it 'Rule of law.'