The importance of larval dispersal in the deep ocean is generally acknowledged in studies of genetic connectivity, conservation, and population ecology, but our understanding of the underlying reproductive, developmental, and oceanographic processes remains rudimentary. Recent efforts at modeling deep-sea dispersal have generally taken the form of sensitivity analyses, because biological parameters for the models are lacking. In this review, what is known about the evolution of biological parameters that may influence dispersal times, depth distributions, and trajectories, including modes of development, vertical ontogenetic migration, are examined, as well as the ecological release from predators enabling slower developmental rates and longer dispersal times. Phylogenetic constraints are important in many groups, yet there are modifications in larval form, developmental mode, egg flotation, parental investment, and reproductive timing that appear to be unique to the deep sea and that influence dispersal. For instance, larval duration in certain taxa is longer in the deep-water species than in many shallow-water relatives.