Field performance of sub surface drainage systems Installed on farmers fields at four different locations were studied In terms of changes in soil salinity, hydrologlcal parameters and crop yield. Results indicated that sub surface drainage system had positive effect on soil physico-chemical properties, hydrological parameters and crop yield. A considerable reduction in soil salinity resulted in improvements of crop yield suggesting the need of sub surface drains for reclaiming saline vertisols. Based on its economic analysis, pay back period of the system ranged from 2 to 5 years indicating the sub surface drainage system is remunerative and cost effectives.