ABSTRACT This paper examines the influence of vehicle usage pattern on the CO2 emissions of a small passenger car, using a correlated drive-cycle simulation. A variety of drive-cycles will be used to illustrate how variation in daily driving range and mean vehicle speed influence the optimum driveline configuration. Several interesting driveline configurations, including series and parallel electric hybrids, are analysed using a variety of logged usage patterns and legislative drive-cycles. The results show which vehicle architecture yields the lowest tail-pipe CO2, well to wheel CO2 and total life-cycle CO2.