The International Risk Governance Council (IRGC) was a nonprofit foundation, based first as an independent, freestanding Swiss foundation in Geneva from 2003 to 2012, and then affiliated with École Polytechnique Fédérale de Lausanne in Lausanne from 2012 to 2023. IRGC's mission was to identify and improve the governance of emerging and systemic risks that have, or could have, impacts on human and environmental health, the economy and society, and overall sustainability. In this paper, we recount IRGC's history, describe its many reports, workshops, and conference activities (including tables referencing the many published products), and provide six brief case histories of accomplishments and insights on work IRGC has done on solar radiation management, small modular reactors, synthetic biology, autonomous vehicles, resilience and systemic risks, and international comparison of risk governance. The paper concludes with some brief observations about the impact of IRGC's work and notes the continuing need for a neutral convening entity that can perform a role similar to that of IRGC.