In today's fast growing automobile world, the Emission limits are stringent; customer expectations of vehicle performance and Fuel economy are more. Achieving these parameters for the given engine are challenging task for any automobile engineers. BS4 Emission limits are 50% more stringent than BS3 limits and from April 2010 onwards, all passenger cars which will be selling in 13 metro cities in India should be BS4 emission compliant.In this paper, we have described how BS4 limits were achieved in a MPV with 2.49 l, 70kW Common Rail Direct Injection Turbocharged Diesel engine, with push rod. During Emission development, the following processes were followed to meet BS4 emission limits without sacrificing the engine performance, Fuel Economy and Noise.Selecting suitable hardwares like Turbocharger, EGR cooler at engine level to reduce NOx and Unburned Hydrocarbon Emissions with best Brake specific fuel consumption.Innovative way to select the EGR Valve size based on Turbocharger performance. Effect of number of holes in injector for Emission and performance.Optimization of injection parameters using BOSCH 2nd generation Common rail Fuel Injection system, where Start of injection timing, Fuel injection pressure, Pilot injection quantity and Position of Pilot injection can be varied to get lesser emission with lesser Brake Specific Fuel Consumption (BSFC).Engine full throttle performance optimization with selected after treatment devices to cater Back pressure effect.Selection of after treatment devices like Catalytic converter at vehicle level and positioning the same for better HC & CO conversion.Fine tuning of Injection parameters at Vehicle level to meet BS4 emission limits comfortably and achieving fuel economy.Drivability and Noise Optimization at vehicle level with emission compliant parameters.Cold start ability optimization with selected hardware's and evaluation of vehicle in all environmental condition (High altitude, winter and summer trials).With this approach, BS4 emissions were achieved with Fuel economy, drivability and NVH same as BS3. It means the end customer is not affected from performance point of view due to BS4 emissions. This approach has proven to be the cost effective as well as robust, for BS4 level.