In this paper, we explore and discuss the use of the concept of being affected in biomedical decision making processes in Germany. The corresponding German term 'Betroffenheit' characterizes on the one hand a relation between a state of affairs and a person and on the other an emotional reaction that involves feelings like concern and empathy with the suffering of others. An example for the increasing relevance of being affected is the postulation of the participation of people with disabilities and chronic or acute diseases in the discourse, as partly realized in the German National Ethics Council or the Federal Joint Committee. Nevertheless, not only on the political level, the resistance against the participation of affected people is still strong; the academic debate seems to be cross-grained, too. Against this background, we explore the meaning and argumentative role of the concept of being affected as it is used by affected and lay people themselves. Our analysis is based on four focus group discussions in which lay people, patients and relatives of patients discuss their attitudes towards biomedical interventions such as organ transplantation and genetic testing. This setting allows for a comparison of how affected and non-affected people are concerned and deliberate about medical opportunities, but also of how they position themselves as being affected or non-affected with respect to (scientific) knowledge and morality. On this basis, we discuss the normative relevance of being affected for the justification of political participation.