Social media make fast inroads into organisations. This raises issues regarding self-presentation and locating experts in these new emerging communication spaces, as the basis for effective social media-enabled knowledge work. However, research on self-presentation and identity in organisational social media is only just emerging and has been founded on broader understandings from studies of public social media. In this literature study we demonstrate that the existing body of research on identity in social media is dominated by a ‘representational lens’. Based on an analysis of the historic foundations of this stream of research, we will expose limitations of this lens in capturing contemporary engagement in online spaces and advocate for a ‘performative lens’ in studying identity work in organisations. We contribute a detailed exposition of the evolution of identity studies in the context of public social media, and we offer an alternative lens for studying the topic in organisational contexts.