The Bunyaviridae is a large and diverse family of viruses whose members infect a wide range of arthropod vectors and animal or plant hosts. Bunyaviruses are distributed worldwide and their promiscuous use of an impressive variety of arthropod vectors amplifies the potential for bunyaviruses to increase their prevalence and geographic range given the right environmental or man-made conditions. Most bunyavirus infections are asymptomatic or present with a mild influenza-like illness. However, some members of the family are important human and veterinary pathogens that are the causative agents of devastating illnesses, including hemorrhagic fever, pulmonary disease, congenital abnormalities, and fatal encephalitis. In this chapter, we discuss the epidemiology, lifecycle, molecular biology, neuropathogenesis, and prevention and treatment strategies for emerging bunyaviruses that are predominantly associated with central nervous disease; these include members of the genera Phlebovirus (Rift Valley fever virus and Toscana virus) and Orthobunyavirus (La Crosse virus and Cache Valley virus).