Some viruses induce, in the infected cells, the formation of cytoplasmic inclusions that are known to contain viral proteins. These viral inclusions that share some characteristics of aggresomes have been considered as sideproducts of the infectious process without any role and resulting from the accumulation and aggregation of large quantities of proteins produced in excess during infection. However, recent results obtained on some viral families suggest that these inclusions have different functions: they can be sites of specific degradation of antiviral proteins or viral factories where essential viral steps (transcription/replication, translation, viral assembly) take place. It is supposed that the viruses-induced compartimentalization is the result of cellular defense mechanisms, which would be diverted by virus for their own replication.