AbstractGreen architecture, engineering, and construction (AEC) projects are deemed more complicated compared with their traditional counterparts. They have been reported to have relatively more frequent delays and higher cost growth. The AEC literature has repeatedly highlighted the importance of leadership for sustainable design and construction and the need for team integration for optimal outcomes. However, studies exploring leadership in the context of green AEC projects are limited. Transformational leadership is a highly regarded theory that is known for its potential to effectively facilitate team integration. This empirical study tests the role of shared transformational leadership received by team members in improving team performance through team integration for green AEC project teams. We collected data from 103 individuals working in nine Leadership in Energy and Environmental Design (LEED) projects in the US. We analyzed the data using structural equation modeling (SEM). Our findings suggest that transformational leadership received by team members is positively related with perceived team performance, and this relationship is mediated through perceived team integration. The study is a pioneer in examining leadership for sustainability and mediation effects of team integration in the AEC literature. The outcomes urge for a change in green AEC project teams to think beyond project delivery systems and practices and incorporate transformational leadership across organizational and communicational tiers of project teams through team procurement, project management, and skill development and training.