Networks are a subject of growing research interest. Yet union networks, particularly networks of delegates, and ways to build them, are still poorly understood. This is a study of the meaning that workplace union delegates assign to networks of support. It explores the characteristics of effective delegate and union networks and influences upon them. Effective networks are a combination of strong and weak ties, such that delegates sometimes do not recognise they are part of a network. Our three-stage research methodology involved delegate focus groups, a paper-based self-completion questionnaire of recently trained delegates (N=473) and a follow-up telephone survey (N=145). It found that organisers were key to creation of internal workplace networks (although they did not necessarily establish them) and in providing a bridge for delegates with external networks. They were the key support person for many delegates. Networks took a variety of forms. Only a minority were formalised. A majority were mainly internal to the workplace. Social media were rarely used, with little intention of using them more, and were, we suspect, underutilised.