Durham School Services is a provider of school transportation services. The company operates more than 11,000 school buses and serves more than 300 school districts in 27 states across the country. It offers transportation services for several special events, including field trips, sporting events, charter trips and day outings. Durham School Services has a staff of trained and certified professionals that specializes in routing, scheduling, detailed billing, budgeting and student discipline management services. The company designs and conducts preventive maintenance programs and has also received the Agency Clean Air Excellence Award for participation in the Diesel Solutions Program. Durham School Services is a division of National Express Corporation, which offers transportation management services.