How can business ethics theories be leveraged to address the challenges and complexities associated with Multi-Stakeholder Initiatives (MSIs), particularly in terms of input legitimacy, institutionalization dynamics, and impact assessment? Furthermore, how might theoretical frameworks such as deliberative democracy theory, deontological reasoning, and integrative social contracts theory enhance our understanding of MSIs’ norm justification processes, motivations for adoption, and moral legitimacy criteria for assessing impact? Considering the diverse perspectives and moral principles involved in evaluating MSI outcomes, how can Boltanski and Thévenot’s theory of justification aid in reconciling conflicting assessments and resolving disputes regarding the moral legitimacy and effectiveness of MSIs in promoting positive societal outcomes while upholding human dignity?