Purpose: Trade unions, like many other membership-based social movement organisations, are confronted by the challenge of growth and revitalisation. Declining membership numbers, an increasingly restrictive legislative framework, and dramatic changes in modes of employment have combined to challenge many unions to rethink the way they work. In response to these challenges some unions adopted what has been referred to as the "organising model", comprising new methods of recruiting, campaigning, educating, fostering activist members, and developing community and international alliances. It is changing the way union staff work, and requires a new understanding of their roles. The purpose of this paper is to examine an organising campaign conducted by one of Australia's largest unions. Design/methodology/approach: The paper draws on semi-structured interviews with a pivotal group of lead organisers, union reports and planning documents, participant observation, and published data on the major private child-care employer. Findings: The efforts to organise the child-care workers proved successful and a new collective agreement was endorsed, confirming for the union that its approach could work. However, the model remains new and whether it achieves the desired outcomes of changing the culture and ways of union work, creates new learning opportunities and activates new layers of workers, is yet to be seen. Originality/value: There is a burgeoning literature on new organising approaches. There are fewer detailed descriptions of the practice of organising and its impact on organisational change and learning. Therefore case studies such as this, which locate the decision to organise this sector, reports on how the campaign unfolded, and discusses the union's interest in understanding the learning associated with these new ways of working, provide an opportunity to examine connections between the theories and practices of organising. (Contains 5 notes.)