Understanding how brands should operate on social media is very important for contemporary marketing researchers and managers. This paper argues that due to the social and networked nature of social media it is an ideal environment for brand communities. Taking a deep qualitative approach and with analysis of a vast array of data, the article articulates the existence of brand communities on social media. More importantly, it delineates five unique and relevant dimensions of brand communities based in social media. The authors advise researchers to consider these dimensions while conducting research on brand communities and social media. Further implications for practitioners and researchers are discussed.