This research examines the learning stimulated through professionals/practitioners working inter-professionally, as multi-agency teams, within Children's Services. Collaborative and inter-professional working have witnessed much attention in recent years. As such hybrid organisational forms become the norm across the sectors, this empirical research typifies the broader challenges facing contemporary organisations across the developed economies. Within the public sector, particularly health and social care, these 'best-practice' configurations have been prevalent for some decades; the 2003 Laming report extended this across the Children's Workforce. However, despite the espoused benefits of this approach, success has wavered. Indeed, a growing corpus of both research and inquiries evidence the failings, accentuating the need for new learning within these teams. This research examines the creation of new knowing-in-practice within the multiagency teams of a case-study North-West England local authority's Children's Services. By contrast to previous research that has demonstrated how learning might occur, this research is focused upon what this learning actually is. Juxtaposing governments' techno-rational approaches to knowledge acquisition, the research uses situated learning theory to better understand these professionals'/practitioners' learning. This lens asserts that learning does not only constitute what one needs to 'know', but also what one needs to 'be'. A qualitative and largely inductive approach was adopted, with data generated through photo-elicitation interviews undertaken with 25 purposively selected professionals/practitioners from across the authority's Area Teams. The findings indicate a number of different 'tales' told by the participants. Despite variations in participants' perceptions, it was generally accepted that multi-agency working was vital in the current socio-economic climate. They emphasised the importance of structures, and of the Team Leaders, in engendering and sustaining learning. However, the significance of agentic influences, especially individuals' commitment to informally develop their 'relational-expertise', were also accentuated. Evidence presented indicated how these professionals/practitioners had experienced significant 'identity-work', developing a distinctive multi-agency team identity alongside their existing professional/practitioner identity. The research fills an important gap in the literature, providing empirical evidence of relationships and learning within multi-agency teams. It refines and extends perceptions of learning through its examination of a context more typically associated with conflict and tension, difference and change rather than those that stressing constancy of practice. This extends understanding of workplace learning across boundaries.