As a step toward a pollution-free environment, governments and regulatory bodies worldwide are moving toward cleaner means of transportation. A lot of tailpipe emissions occur in a conventional internal combustion engine. One solution to these hazardous emissions is the use of hybrid-electric vehicles (HEVs) or fully electric vehicles (EVs). The HEVs, especially plug-in HEVs (PHEVs), are soon expected to have more significant commercial applications, as the EVs may take more time for their larger part of the share. A hybrid-electric vehicle employs an IC engine combined with a smaller battery and an electric motor. On the other hand, a PHEV consists of a much larger capacity battery storage known as a rechargeable energy storage system (RESS). It is equally important to apply a stable drivetrain topology for greater efficiency. PHEV blends power from battery and engine using an energy management system, which always tries to impart the best driving conditions, least emissions, and maximum mileage and range. In the paper, an overview of all the control strategies is reviewed with few simulation results.