International trade has often played a crucial though not necessarily benign in the historical development of the third world. Neoclassical theory of trade since Adam Smith and David Ricardo has emphasized the virtues of comparative advantage and noninterference in international trade. Such Adherence to free trade promotes the maximization of welfare for the world and member countries in the world trading system. But, Given the level of poverty in developing nations and what they see as special problems confronting them, developing nations sometimes judge the free trade as neoclassical theory stated as inappropriate and it may not the best policy for them.A deep and abiding concern with global international relations flourishes even more today, not only because of the still bitter controversies between "trade optimisms" that advocates free trade and "trade pessimism" that advocates less, especially in the context of development, but also because modern transport and communications are rapidly shrinking the world to a "global village". The objective of this paper is to focus on traditional and more contemporary theories of international trade in the context of particular importance to developing nations.