Based on the available energy sources, the electric vehicle (EV) cannot compete with the conventional vehicle in terms of driving range and initial cost. In the near future, the hybrid EV (HEV) is not only an interim solution for implementation of zero emission vehicles but a practical solution for commercialization of super-ultra-low-emission vehicles. This paper firstly presents an overview of latest HEVs, with emphasis on power management. Based on the power management strategy of the drive train, a new classification approach for HEVs is proposed. Hence, the corresponding system configurations are identified. The power flow control for various HEVs is also elaborated. Finally, the development trends of HEVs and EVs are delineated.