This paper discusses how active mounts can reduce vibration and noise caused by engine vibration in vehicles. In recent years, vibration and noise problems have been exacerbated by the trend towards lighter, more fuel efficient vehicles. The connection of more powerful engines with fewer cylinders to lighter vehicle frames has resulted in vibration problems that passive elastomeric and hydraulic mounts cannot adequately address. Active mounts, which consist of passive mounts, force generating actuators, sensors, and electronic controllers, can achieve significant performance improvements over passive mounts. The superior vibration isolation capabilities of active mounts may also allow for the elimination of the engine's balance shaft, reducing engine weight, height, and cost, and helping to achieve further fuel efficiencies. In this paper, several different active mount configurations, actuation technologies, and sensor and controller choices are discussed. Also, a mount effectiveness analysis demonstrates the performance improvements of active mounts versus passive elastomeric and hydraulic mounts.