Nineteen scientists from different disciplines collaborated in highlighting new methodological and theoretical aspects in the re-emerging study area of fission-fusion dynamics. The renewed interest in this area is due to the recognition that such dynamics may create unique challenges for social interaction and distinctive selective pressures acting on underlying communicative and cognitive abilities. In five sections, we outline new frameworks for integrating current knowledge on fission-fusion dynamics and suggest promising directions for future research using a broad comparative perspective. In the first section, we briefly review the diverse uses of the term “fission-fusion” and propose a fundamental re-thinking away from its current general use as a label for a particular modal type of social system (i.e., fission-fusion societies). Specifically, because the degree of spatial and temporal cohesion of group members varies both within and across taxa, we note that any social system can be described in terms of the extent to which it expresses fission-fusion dynamics, and we thus advocate a realignment of use of the term “fission-fusion” to reflect this perspective. The implications of this perspective are then discussed and expanded in three sections focusing on the socioecology, communication, and cognitive demands of fission-fusion dynamics. The last section explores the relevance of fission-fusion dynamics for human social evolution.