David W. Casper, P.E., is a senior vehicle engineer and program manager at STV with experience directing activities related to the design, manufacturing and introduction of more than 2,000 vehicles into service. He has expertise in bus vehicle technology and the planning and procurement of energy-efficient and environmentally responsible buses, including clean diesel, hybrid, zero emission trolley bus and ZEB fleets. His background also includes extensive overhaul/modernization programs for commuter rail, rapid transit and light rail vehicles. He is also one of the developers of the PEER modelling program.