Green manuring with Sesbania aculeata is a widely investigated practice in cereal-based cropping systems but adoption of this technology is low on farmers' fields because of some practical and economic considerations. Dual-purpose legumes such as cowpea (Vigna unguiculata) and greengram (Vigna radiata) providing economic produce as well as stover for incorporation are a viable alternative for effecting N economy and enhancing crop productivity. Direct and residual effects of different legumes along with varying rates of N fertilizer were evaluated on productivity, profitability, N-use efficiency and residual soil fertility in maize-wheat cropping system at New Delhi during 2003-2005. The legumes, viz. cowpea, greengram and Sesbania were grown during summer (April/May to June), followed by maize in rainy season (July to October) at varying rates of N fertilizer, viz. 0, 40, 80 and 120 kg ha −1 ; and wheat in winter season (November to April) at 0, 60 and 120 kg Nha −1 . Cowpea and greengram produced equal amount of economic produce (1.22-1.27 t ha −1 seed yield equivalent), which added 3.26 t and 2.79 t ha −1 of stover, and 49 kg N and 47 kg Nha −1 respectively into the soil. However, Sesbania accumulated maximum amount of biomass (4.75 t ha −1 dry weight) and N (131 kg N ha −1 ). Growth and yield of maize following summer legumes improved compared with that after fallow, and was maximum after Sesbania, followed by greengram and cowpea. Response of maize to N fertilizer rates was quadratic and there was saving of N to the extent of 57-67 kg ha −1 with Sesbania, and 37-49 kg ha −1 with cowpea and greengram. Wheat also performed better under the residual effect of summer legumes, and showed N economy of 18-23 kg ha −1 after cowpea and greengram, and 27 kg ha −1 after Sesbania. Nitrogen fertilizer applied to maize had only a marginal residual effect and direct N application was necessary to achieve the potential yield of wheat. Apparent recovery of N showed a decreasing trend with summer legumes and increasing rates of N fertilizer. There was significant improvement in soil organic C and KMnO 4 oxidizable N after two cropping cycles with summer legumes. Despite higher yields and large N savings, Sesbania green manuring resulted in lower net returns on par with fallow, while greengram or cowpea followed by maize and wheat were found to be the most profitable cropping systems. It was recommended that cultivation of dual-purpose legumes during summer was a better option than Sesbania green manuring or fallow for improving productivity, profitability, N economy and soil fertility, leading to sustainability of maize-wheat cropping system.