Abstract
This paper develops a dialectic process model to explain how group norms evolve in self-organizing open online communities. Archive data collected from a celebrity fandom community is used for a netnography study that is complemented by an interview with the community administrator. The analysis of the data reveals that the fluidity of online communities triggers changes on norm conformity leading to increased peer to peer moderations. That raised contradictions on norm schema (clarity and alignment with the community identity). I find drivers that affect the resolution of norm contradictions. This paper develops an iterative model to explain how norm contradictions are continuously raised due to fluidity and resolved by community members. The findings have theoretical and practical implication on the sustainability and fluidity of online communities from group norm perspective.