This chapter summarizes the results of the previous chapters. It underlines that the category of rare diseases was invented to help orphan drugs be marketed again, and not the other way round. It discusses the role of rarity in patients’ illness experience, highlighting the importance of care and isolation for the patients. It discusses biosociality in rare patients’ experience, as daily issues and maintaining relationships tend to have priority over a biological view of the disease. This chapter ends with a discussion of Georg Simmel’s analysis of the dynamics of small groups. Simmel hypothesized that small groups could develop a particular type of radicalism, that he called “sociological radicalism”. It seems that the diversity of small groups could be another important dimension of their life.