Organisations can be understood as organisms exhibiting a formal structure formalised by the “org chart”, and informal structures of emerging networks between employees. The increasing use of Enterprise Social Networks (ESN) provides mangers and researchers with new opportunities to uncover formal and informal structures. Yet, it remains underexplored what exactly constitutes relationship structures in ESN. We employ the notion of ‘digital traces’, stored as user-generated data on the ESN and set out to explore ways for conceptualising relations as the basis for network constitution and visualisation. We illustrate our approach with a case study of an ESN and demonstrate how resulting networks vary significantly depending on the digital traces employed.