This article shares specific leadership findings from the evaluative study of action research AR (ESAR). Few studies have examined the leadership dynamic within action research (AR), and fewer still across multiple projects. Leadership surfaced as a critical element in the ESAR as we sought to examine processes, outcomes and impacts of AR at a meta level. Evidence was collected from six AR case study projects via interviews, survey, goal attainment scaling and documentary analysis, followed by a survey issued to 195 projects internationally (174 responded), that is, all of the projects recruited and compiled in our ‘Directory’ at the beginning of the ESAR. The findings revealed that leadership was more collaborative than hierarchical though there was evidence that a single key person leading was pivotal to enhancing processes, outcomes and impacts of the AR projects. In this article, we offer new thinking about leadership elements that enhance AR as well as contribute to the growing conversation about shared, collective and relational approaches to leadership situated within AR systems.