To meet future emission levels, the industry is trying to reduce tailpipe emissions by both, engine measures and the development of novel catalytic emission control concepts. The present study will focus on the close coupled SCR on Filter commonly known as SDPF which is a main pathway to reduce NOx along with Particulate mass and number for light duty passenger cars and sport utility vehicles for BS 6 RDE/OBD 2 and future legislation like BS-7. SDPF is a challenging technology as it is critical component in exhaust after treatment system involving in NOx and PM/PN reductions hence careful optimization of this technology is necessary in terms of Space velocity requirements, Temperature profile wrt to NOx conversion, Raw NOx concentration, Particulate mass and Ash holding capacities, NH3 storage requirements, back pressure and so on. With BS6 RDE having extremely challenging CF for NOx equals to 1,43, the SDPF design & optimization is high on importance and to demonstrate the success of SDPF it needs critical design process involving modelling, synthetic gas bench and Engine bench testing followed by vehicle testing. This procedure ensures the SDPF performance with different input conditions and can be verified before actual hardware testing begins. Umicore always strive to design the catalyst not only for legislative cycles but ensure that these systems work well till the end of the useful life. Hence this paper represents a joint study between Umicore and ERC-Tata Motors for SDPF design and optimization through state-of-the-art DOE methodology for Space velocity and NOx performance using MATLAB® software and validation on synthetic gas bench. In future, this study will be further augmented with engine bench testing at ERC-Tata Motors for performance evaluation and optimization through DOE tools. SDPF is clearly the main pathway of clean mobility solutions for diesel passenger and SUV segments and hence the content of this paper will help in assisting SDPF design and optimization for clean air. Keywords: BS 6, BS 7, Emissions ,RDE,OBD, DOE, SDPF, SCR, CF, Durability