Viruses count amongst the most amazing organisms on Earth regarding their evolutionary and adaptive abilities. They resort to several different forms of coding information in their genomes; together with an array of different mutational mechanisms, they have succeeded in infecting all cellular organisms and in escaping any antiviral strategy (natural or artificial). We will present and discuss a puzzling example of viral adaptive strategy: viruses with multipartite genomes. Multipartite viruses possess fragmented genomes with fragments encapsidated in independent viral particles. This demands co-infection of cells to complete the viral cycle, a condition that poses severe restrictions on the number of viral particles infecting single cells. This kind of viruses infects mostly plants and represents about 16% of all viral species described. As of today, the adaptive advantage of multipartition in front of complete or fragmented genomes encapsidated in a single particle remains undisclosed.