Caulimoviridae is one of the three families of plant-infecting viruses which employ reverse transcription of their transcripts to replicate their genomic DNAs. Other families include Metaviridae and Pseudoviridae ( https://talk.ictvonline.org/taxonomy/ ). Members of the family Caulimoviridae are identified by the presence of non-covalently closed circular dsDNA genome with icosahedral (50–52 nm) (members of the genera Caulimovirus, Cavemovirus, Petuvirus, Rosadnavirus, Solendovirus, and Soymovirus) or bacilliform (30 nm × 130–150 nm) (members of the genera Badnavirus and Tungrovirus) shape without any envelope (Table 7.1). Virions of this family have buoyant densities in CsCl of 1.37 g cm3 (genera with isometric virions) or in CS2SO4 of 1.31 g cm3 (genera with bacilliform virions). Sedimentation coefficient of the virus particles (S 20) is generally between 200S and 220S. The virions are very stable between pH 4 and pH 9 and in high salt concentrations (ICTV 2018). There is a single molecule of non-covalently closed circular dsDNA of 7.2–9.2 kbp with discontinuities at specific places in virions: There is one discontinuity in the minus-strand and one to three in the plus-strand. Viruses of the family affect a wide range of plants that include monocots and dicots, while isolates/strains of a single species have usually limited host ranges. Some viruses in the family cause severe losses in many tropical and subtropical crops. For badnaviruses, caulimoviruses, and tungroviruses, insect vectors have been identified. For badnaviruses, caulimoviruses, cavemoviruses, petuviruses, and solendoviruses, endogenous viral elements (EVEs; viral DNA integrated into the host nuclear genome) are known. Some caulimovirid EVEs in Musa balbisiana, Petunia hybrida, and Nicotiana edwardsonii are known to be replication competent and can lead to spontaneous infections by episomal forms of the viral genome when exposed to biotic or abiotic stresses. Although caulimovirid EVEs are widespread in the genomes of vascular plants, the majority of them are thought to be replication-defective.