ABSTRACT
Theory of mind (ToM)—the ability to attribute mental states to oneself and others—is a core social-cognitive skill that develops throughout childhood and adolescence. This systematic review synthesises 337 studies with 89,111 participants from 39 countries to organise the literature. We propose a six-domain ecological model encompassing within-child factors, family, peers, educational settings, community contexts, and culture. Research has heavily focused on within-child factors, especially executive functioning, language, and emotional understanding, which are consistently linked to preschool ToM. In contrast, advanced ToM and later developmental stages remain underexplored. Family and peer influences show meaningful but varied associations. Educational settings may promote ToM through inclusive practices and teacher behaviours, although findings are sparse. Cultural mechanisms are rarely examined beyond group comparisons, and community-based influences are nearly absent. We highlight major gaps and call for longitudinal, context-sensitive, and cross-cultural research to better inform interventions supporting children’s social, emotional, and academic development.