Positive-strand RNA viruses include the majority of the plant viruses, a number of insect viruses, and animal viruses, such as coronaviruses, togaviruses, flaviviruses, poliovirus, hepatitis C, and rhinoviruses. Works from more than 50 leading laboratories represent latest research on strategies for the control of virus diseases: molecular aspects of pathogenesis and virulence; genome replication and transcription; RNA recombination; RNA-protein interactions and host-virus interactions; protein expression and virion maturation; RNA replication; virus receptors; and virus structure and assembly. Highlights include analysis of the picornavirus IRES element, evidence for long term persistence of viral RNA in host cells, acquisition of new genes from the host and other viruses via copy-choice recombination, identification of molecular targets and use of structural and molecular biological studies for development of novel antiviral agents.