Polydnaviruses do not replicate in the traditional sense of virus replication, which is one reason they have not usually been included in comprehensive reviews on DNA virus replication. Whereas in all other cases infection of host cells would lead to production of progeny virions, polydnaviruses instead have evolved by anomalous lifecycle and replication strategies requiring two insect hosts. The replication of polydnavirus DNA and packaging and production of progeny virions are limited to certain specialized cells found only in females of the parasitoid wasps where they are produced and harbored. Furthermore, replication is directed by a linear provirus form of the virus, integrated within the parasitoid wasp chromosomes. Finally, genes for most, if not all, virion structural proteins are not packaged into polydnavirus particles. Our understanding of the unique attributes of the polydnavirus particle, its formation through novel replication and life cycles, has been limi! ted. This brief review summarizes current replication models, and underscores the need for further research. With additional genomic information, including comprehensive analyses of the integrated provirus form, the mechanisms employed during polydnavirus replication and infectious virus particle formation may be clarified none2006