This book offers the first comprehensive, empirically grounded analysis of how corporate human rights and environmental responsibilities are conceptualised, interpreted, and operationalised through OECD National Contact Point (NCP) case law. Moving beyond doctrinal debates, it examines 394 specific instances handled between 2000 and 2024 to demonstrate how NCP statements function as an evolving body of quasi-juridical authority that progressively shapes the meaning, scope, and content of the corporate responsibility to respect under the UN Guiding Principles on Business and Human Rights (UNGPs) and the OECD Guidelines for Multinational Enterprises. Combining traditional legal analysis with systematic content analysis using MAXQDA, the book traces how norms are articulated across all dimensions of human rights due diligence: policy commitments, risk identification, prevention and mitigation, tracking, communication, remediation, and stakeholder engagement. Each thematic chapter distils key findings from the case law, highlighting both best practices and persistent shortcomings, and showing how companies navigate complex questions of causation, leverage, and corporate involvement in harm—whether through their subsidiaries, supply chains, investment relationships, or broader business structures. The book further clarifies corporate responsibilities in context: gender-based impacts, workers’ rights, Indigenous Peoples’ rights, minority protection, environmental harm, climate impacts, conflict-affected areas, and alignment with the Sustainable Development Goals. A dedicated analysis of different corporate actors—parent companies, investors, financial institutions, non-profit organisations, and state-owned enterprises—reveals distinct patterns of accountability and influence within transnational economic activity. Finally, the book turns to the state duty to protect, offering a critical examination of how home states regulate extraterritorial corporate conduct, the forms of complicity that emerge, and the regulatory measures reflected across NCP practice. The conclusion argues that, taken cumulatively, NCP statements amount to a significant and under-recognised source of normative authority: a soft-law mechanism whose interpretive influence is shaping the future direction of corporate human rights and environmental responsibility.