Grand challenges require coordinated and integrated responses that draw on different occupational communities’ competencies that might otherwise remain in isolation. We theorize how grand challenges can be tackled by mobilizing landscapes of practice – a totality of local communities that constitute a ‘living knowledge area’ within a given domain. The landscapes of practices concept helps to understand the deployment of participatory architectures, which in the current literature is considered essential for addressing grand challenges. To this end, landscapes of practice emphasize the mutual accountability between networks and communities across informal and institutional settings and the need to learn about the landscapes of practice rather than focusing only on developing local competencies. Thus, landscapes of practice mobilization is complex and requires collective practical judgment while facing the arising socio-political tensions. Drawing on a study focused on Australian mental health care, we propose four pillars enabling the mobilization of landscapes of practice, and constituting general guiding principles – determining and legitimizing the landscapes of practice’s purpose, deploying landscapes of practice-based governance structures, motivating and connecting membership across the landscapes of practice, and demonstrating the value of the mobilized landscapes of practice. Thereby, we propose a framework of mobilizing landscapes of practice that serves as a reference for network leaders and managerial practice while advancing the academic debates on grand challenges and situated learning.