Boundaries, which are essential for the healthy functioning of individuals and organisations, can become problematic when they limit creative thought and action. In this article, we present a framework for promoting health across boundaries and summarise preliminary insights from experience, conversations and reflection on how the process of boundary spanning may affect health. Boundary spanning requires specific individual qualities and skills. It can be facilitated or thwarted by organisational context. Boundary spanning often involves risk, but may reap abundant rewards. Boundary spanning is necessary to optimise health and health care. Exploring the process, the landscape and resources that enable boundary spanning may yield new opportunities for advancing health. We invite boundary spanners to join in a learning community to advance understanding and health.