The proceedings at hand include the contributions of the speakers of the 4th Symposium Hybrid Vehicles and Energy Management 2007. The Symposium is organised by the GZVB - Traffic Transport Telematics together with the Center of Transportation of the Technical University of Braunschweig, in cooperation with the IAV GmbH and supported by the Federal Ministry of Economics and Technology. For the first time in 2007 a DEUFRAKO Workshop „Clean Vehicle“ is included.