This paper introduces the concept of self-defining groups to explain how personal and social aspects of identity relate to each other among members of an extreme right-wing political party. Two studies were conducted. Study 1 examined how affiliation with a social group that has clear-cut, rigid norms and values affects the personal and social self-concept. Participants were members of a (self-defining) Turkish nationalist organisation (N =66) and a control group of Turkish university students (N =58). Paradoxically, high levels of national identi fication were associated with stronger personal identity. Study 2 used the same participant population (N =177) and manipulated self-focused attention by means of a mirror. Self-aware members reported the highest levels of identification with the nationalist organisation. Results suggest that members of this groups show no signs of ‘vanishing individuality’: although boundaries between personal and social identities are blurred, extremist group members retain a distinct and strengthened sense of personal identity. This raises some interesting questions for the concept of personal identity and how it can be informed by the content of one's social identity.