Existing methodological approaches to business and human rights frequently fail to address the broad spectrum of relevant issues in the field. Persistent disciplinary silos and normative limitations of key legal and governance instruments result in reductive normative approaches and ultimately in ineffective policies. Focusing on the normative environment covered by UN Guiding Principle No. 9, specifically on the intersection between business and human rights in international investment, this paper argues for the need to put forward interdisciplinary socio-legal methodologies. It contends that any comprehensive methodology addressing the field ought to account for the specificity of existing governance models, the intrinsic dominant role of corporate actors and the socio-legal complexity displayed at the intersection of human rights with business and market mechanisms. The analysis developed is advanced not as a ‘model’ methodology but as an instance of mapping out how a relatively narrow governance approach can be enhanced methodologically in order to better inform research and policy design.