Although hybrids are becoming more popular with manufacturers - the technology being a relatively simple, cost-effective way to meet regulation and customer demand for some level of electrification in their next vehicle, plus being easier to develop than a vehicle from scratch - the engineering presents significant issues in terms of packaging, managing heat transfer to other components and addressing the changes in sound when switching between different modes/source of power. Continuing just-auto/AIC's series of interviews, we spoke to Dmitri Konson, Vice President Global Engineering of Tenneco´s Clean Air business group, about active exhaust valve technology and how its use has evolved to become a key part of hybrid exhaust architecture, rather than being a device that has been previously used on many vehicles, particularly those of high performance, to meet noise regulation.