Leadership in Impact Assessments (IAs) should be transformative: i.e., it should exert a positive influence on project and planning or program teams and generate willingness to embrace sustain able outcomes. The key to meaningful outcomes in IA is building trust with diverse disciplinary experts. IA leadership extends the IA process from a technical and regulatory process into a positive approach to achieve wider and more sustainable societal outcomes. The impact of IA is largely dependent on the competence, values and knowledge of its profession als and their willingness to influence and advocate for equitable and balanced development. This requires transformative leadership to guide, influence, and enable the integrated work of the IA team and its outcomes.