Despite its remoteness, the deep sea is not spared from the impact of human activities. The emergence of industrial-scale deep-sea mining of polymetallic nodules on the abyssal plains (4-5 km depth) of the Clarion-Clipperton fracture zone in the equatorial Pacific is potentially the most threatening undertaking at present time. A primary aspect that must be comprehensively assessed in order to safeguard these abyssal benthic communities through the designation of marine protected areas and the spatial organization of prospective mining fields is connectivity, i.e., the continuity of species distributions in space and time. In this review we provide the current state of knowledge on connectivity through an examination of published literature focused on several animal groups from all benthic faunal size classes (megafauna, macrofauna, meiofauna) as well as Foraminifera and microbes. We highlight the main challenges associated with assessing connectivity in the deep sea and outline the key parameters required to achieve the idealised connectivity study for fauna and microbes.