Theories of unbalanced growth focus on the implications from unequal sectoral growth and indicate what type of planning is needed for promoting different sectors of the economy for maximizing total economic gain. There is some literature about the inter-regional inter dependencies, exploitation of which would improve the over all regional economic welfare. It is possible to view this problem using the approaches of equi-marginal sub-regional productivities with a purpose to maximize regional productivity. The scarce resources of the regional economy should be so allocated as to achieve maximum regional economic welfare which in turn can be realized if the productivity of the use of the resources in different sub-regions of the region would be equalized. This does not necessarily require equal allocation of resources in all the sub-regions. However, the resources will have to be allocated on the basis of the principle of comparative advantage for region in the use of resources. This book presents various research papers on regional disparity and other related issues.