Stakeholder involvement has been a major re-quirement for effective, efficient, and fair risk goveance. Since risk management includes uncertain outcomes that affect different parts of the population to different degrees it is essential to integrate the knowledge, values, and in-terests of stakeholders into the risk policy making process. The article provides insights into how to structure and or-ganize stakeholder participation and how to cope with the challenges of complexity, uncertainty, and ambiguity. For each of the three challenges there is a need for specific input from stakeholders. The article describes these re-quirements and explains the formats that have been tested for providing this input to the risk goveance process.