The diverse set of studies in this special issue on fathers' play includes empirical research from several countries, observational measures of play, and multiple children's outcomes, including language, negativity, social competence, aggression and internalizing problems. The chief conclusion across studies is that the role of paternal play is important in various domains of child development. This is encouraging, yet also disturbing given the results of the State of the World's Fathers: Time for Action report 2017, revealing the low amount of care fathers provide to their children worldwide, relative to mothers. In this commentary, the measurement and conceptualization of play are discussed, as well as cultural considerations regarding the meaning and consequences of play. The findings of the studies are integrated in order to guide future research, addressing what domains of child development appear to be influenced by what types of paternal play, and discussing the contexts that affect paternal play. Lastly, the collective results are related to recent efforts to increase fathers' involvement and implications for interventions are discussed.