1. Development and Evolution of Neoclassical Contract Law Contract is a legal foundation that governs various social behaviors and relationships. Recent globalization and expansion of market economy have introduced various forms and substances of contract in domestic and international economic activities, which in turn have led to further development in the law of contract. As a result, the law of contract now governs behaviors and relationships beyond its traditional scope, and is increasingly applied to the realms of the civil law and the commercial law and even to the areas of the public law and the societal law. Accordingly, it seems that the law of contract takes a central position in modern law. The legal conception of contract, as understood within neoclassical law - i.e., “an exchange of promises and agreement between two or more parties to do, or refrain from doing, an act, which is enforceable in a court of law” - emerged in Europe since the 17th century and was established in the 19th century. Neoclassical law of contract bases its theoretical ground in the principle of justification that encompasses the principle of the freedom of contract and the principle of private autonomy. In other words, liberalism and individualism is the philosophy of the neoclassical contract law. Neoclassical contract law theory is also called ‘intention theory’ since contract is believed to be based on the intentions of contracting parties who are largely free to set their own terms of agreement - not only the justification of binding contracts but also the basis of dispute remedies have their roots at contracting parties' intentions. However, the four social trends in Europe and America since 1870 - i.e., 1) the advent of consumer sovereignty, 2) the emergence of representative democracy, 3) the growth of society driven by enterprises and labor unions, 4) the appearance of a mixed economy - have facilitated the fall of the theories of neoclassical contract law and had a great impact on the reconfiguration of the system of contract law. 2. Trends in Modern Contract Law and Theory of Justification Now most of contracts are not governed by either civil law or commercial law. This is because, while civil and commercial laws define the overall scope of the law of contract based on the principles of free contract, details of contract are now defined by various special laws, shifting their focus to a set of special laws. They can be broadly grouped into three categories: 1) special laws which purport to directly intervene the process of contract establishment and its substances for the stake of public interests, 2) special laws which directly govern private contracts for the purpose of protecting the under-privileged party, 3) special laws which mandate obligation of information sharing through documentation and enforcement in order to facilitate rational decision-making by contracting parties. Among the contract theories which justify the aforementioned trends and properties of modern law of contract, the two notable ones are ‘reliance theory’ and ‘relational contract theory’. In the reliance theory, “trust” takes the central role in addressing the binding nature of contract, instead of relying on the agreement between contracting parties. According to the reliance theory, the enforceability of contract resides not in mutual agreement, but in trust-based actions which result in either losses or gains to each party. In particular, while the law of excessive profits stipulates the obligation to return unduly profits even without the contractual agreement on such obligation, the law of illegal behaviors mandates the obligation to compensate the damages caused by the breach of trust-based relationships even without an agreement between contracting parties. Relational contract theory focuses on a “relational contract”, such as franchise contract, licensing contract, or transaction contract between corporations, where social relations affect contractual obligations and binding power and where ongoing relationships are required based on reciprocal trust between contracting parties to achieve their common goals. This is contrast to other type of contracts which stresses the very intention of contracting parties, such as purchasing a product at a convenient store, while ignoring their social relations or contexts. The reality of contract encompasses the elements of both classical and relational contracts. As such, as long as a contract reflects more of the elements of relational contract than classical contract, it should be governed by the principles of relational contract. The court of law in Germany, Switzerland, and Japan has made early applications of a general principle of trustful-faithfulness into the rulings that extend contractual liabilities. It is argued by the advocates that such efforts intend to address the shortcomings of classical law of contract and to advance the parallel development of new system of contract law which incorporates both the principles of classical law of contract in market transactions and the spirit of relational contract theory as internal substantive norms. 3. Expansion of Commercial Contract Ancient codes of Hammurabi defined various commercial behaviors, such as sales, deposit, debit and credit, mediation, and agency, and included the regulations on an order of payment and a title of debt. However, they differs from modern conception of contract in that ancient codes did not acknowledge the right to privately own properties or the right to freely contract between merchants or between a merchant and a consumer. It seems that they were limited mainly to penal clauses governing the breach of contract law. The emergence of centralized power of nation enabled first codification of commercial law in 1807, namely, Code de Commerce in France. Since its inception, commercial law had been considered a special law which was applicable only to merchant classes. However, with the codification of commercial law, it evolved into a general law which governs all kinds of commercial behaviors by the general public as listed in the codes of commercial law. The market economy and international trade, which started with geographical discovery and industrial revolution, have made a rapid development and created large corporations with huge capital, further resulting in the emergence of global monopolies in industries. As a result, it has been proposed to establish a international institution to remedy the abuses of monopoly and to develop an over-arching unified body of rules and regulations to govern international trade. 4. Globalization and the Integration of the Contract Law Our times are characterized by advanced technology and science, information and globalization. Especially, glolbalization of world economy has made rapid progress driven by the collapse of socialism and planned economy and by the elimination of barriers among nations through organizational efforts of GATT, WTO and FTA. Whilst globalization has been further accelerated by the free trade of product, capital, technology, resource, and labor, becoming a truly integrated global market requires a unified international trade law. Europe is at the brink of establishing an integrated economy among the member nations of the European Union (EU). To support this movement, drafts for a uniform code of civil law and a commercial law is in preparation by the member nations of the EU. The revision of the liabilities law of Germany in 2002 was made possible by EU’s acceptance of transaction guidelines for consumer goods in 1999, for the purpose of materializing a uniform contract law among EU member nations. The most notable one among uniform international trade law would be the Convention on Contracts for the International Sale of Goods - i.e., the Vienna Convention of 1988 - which was drafted by the United Nations Commission on International Trade Law (UNCITRAL), and accepted with the validation of member nations. This law is truly uniform in a sense that worldwide experts of contract and trade law have be gathered their knowledge to transcend and explore beyond the differences of Anglo-American Law, Continental Law, and Islamic Law. Although the most typical form of contract in international trade is sales, another exemplary attempt toward a uniform law to encompass all other forms of contracts is the Principles of International Commercial Contracts of 1994, which was first initiated in 1980 by UNIDROIT. This is not a treaty draft or a model law, but rather a “restatement” of principles of the law which applies to international trade. It functions as custom law and reason in international trade, and is utilized as a basis for arbitration which is more commonly adopted to resolve international trade disputes. Since the weight of capital transaction is increasing in international trade, and mega capital and investment funds have dominated the world economy. In consequence, the risk of a few insolvent investment funds to affect the world capital market is much greater than ever. In order to cope with such risk, the establishment of a global cooperative system and the enactment of a unified law governing capital transaction are of utmost importance, now more than ever.