Scaling learning health systems in practice: From interdisciplinary science to system integration

Health systems are increasingly embracing the concept of the Learning Health System (LHS) to address persistent challenges. While there is growing alignment around core principles and components of an LHS, many organizations struggle to translate these ideas into practice. The challenge is not a lack of frameworks or evidence, but the difficulty of organizing existing assets, aligning incentives, and embedding learning into routine governance and workflows, resulting in learning that remains project-based rather than a system-wide capability. Building on our previously published LHS Action Framework, this commentary provides a practice-informed account of how an LHS can be operationalized and incrementally scaled within a large, complex health system. Using Trillium Health Partners as a real-world example, we describe a phased journey from interdisciplinary, project-based learning to early forms of system integration, illustrating how scientific, operational, and relational assets are mobilized into core learning functions. We highlight how early projects generated actionable insights, strengthened collaborative routines, and informed system reorientation, and surface emerging conditions required to normalize learning as an operating model. This paper offers concrete insight into what health systems do to institutionalize learning over time, offering practical guidance for those seeking to move from LHS aspiration to sustained system change.