This study examined how transformational leadership affects job performance among employees in Sport for Development and Peace (SDP) organizations by focusing on the serial mediating roles of shared leadership and job engagement. Survey data were collected from 105 non-executive SDP practitioners worldwide. Results showed that transformational leadership did not directly influence job performance. Instead, it indirectly enhanced performance by promoting shared leadership, which in turn increased employees’ job engagement and ultimately improved their perceived performance. The serial mediation pathway was significant, while individual mediation paths were not supported. These results provide empirical evidence for a process that has been theorized but rarely examined. The study contributes to leadership research by demonstrating that transformational and shared leadership jointly work to shape employee outcomes. It also highlights that leadership effectiveness in SDP organizations should be understood as a multi-layered process. Theoretical and practical implications are discussed for advancing leadership theory in sport management and offering actionable guidance for SDP organizations.