This chapter reviews advances in the use of entomopathogenic viruses as biopesticides in suppressing crop insect pests. It begins by discussing insect pests and their impact on the environment and how insect pest control has developed over time. It also highlights how viruses have been used as potential insect control agents. The chapter first analyses RNA viruses, specifically focusing on tetraviruses and reoviruses. It then looks at DNA viruses, focusing on Parvoviridae, Poxviridae, Nudiviridae and Baculoviridae. As baculoviridae is the most studied group of insect-specific viruses, the chapter also provides information on attributes of baculoviruses, an analysis of baculovirus genomics and molecular biology, a discussion on biopesticide development and reviews baculovirus production and formulation. It also provides a paragraph on the development of host-resistance to baculoviruses. The chapter concludes by providing an overview of how insect-specific viruses have potential for development as biological control agents of insect pests in integrated pest management (IPM) systems.