People in vulnerable situations have the same right as others to participate in public spheres and influence health and welfare services. However, organisations that support these people and promote their interests are essential to their participation. This study investigated how people in vulnerable situations with lived experiences of using public services participate in organisations representing their interests. Fourteen representatives from eight interest organisations were interviewed. The first theme we developed – namely, participation as representatives of the organisations, revealed that a spokesperson’s role is connected to competence and that users of public services rarely obtain such a position. However, people with experience of using public services participate as living examples in external activities, increasing the groups’ visibility through their physical presence and their stories. The second theme was titled participation in organisational activities. The extent to which people with lived experiences participate in formal meetings varies, but they are often consulted by the organisations and attend events and informal gatherings. Notably, people in vulnerable situations interact with and, thus, influence the service-providing organisations. This article discusses the findings in light of representation theory and their implications for practice.