Synopsis The present book is output of research work of many years. The effort is unique in many respects. Different from other efforts on the SAARC, this is a projection of post integration scenario of the South Asian Countries. Beginning with the general observation of the South Asia in terms of social, political and economic indicators, it reviews the issues that have been raised by different studies. As the problem of economic integration is some time studied under the title of Customs Union, it offers an extension of schema provided by the theories. The standard theoretical frame work is unable to explain the events like setting up a common power grid or like building up food reserve. Assuming a free and efficient market mechanism, it evaluates integration of demand and supply separately. It gives post integration equilibrium value of out put and prices over the divisions of five sectors, viz. agriculture, mining & quarrying, transport, construction and manufacturing. Detailed computer programme (Using FOTRAN7)for calculations are given as appendix.