The health care service system is currently undergoing a profound revolution that has put the patient at the core of health outcome co-creation. Patient-centered care could be associated with Service Dominant Logic that looks at co-creation process as a dynamic resources’ integration between actors. From this standpoint, the need for a broader vision of value creation process towards a service ecosystem perspective is emerging. This paper includes an overview of the scientific literature and reports on a narrative case study analysis concerning the "International Consortium for Health Outcomes Measurement" in an attempt to nourish the debate on the different ways that multiple actors can collaboratively shape a health service ecosystem. Findings reveal that co-creation practices, involving multiple actors who belong to different ecosystem levels, led to mutual adjustments and to on-going shared changes. These processes directly influenced health outcome creation, which is reframed in light of patients’ needs, expectations, and experiences. Therefore, patients are assuming the role of health outcome “co-creator”, interacting with all other ecosystems actors (e.g. physicians, institutions, NGOs, health managers, ICTs providers etc.). This study represents a first and preliminary attempt to investigate a real example of dynamic resources’ exchange, based on the contribution of multiple interacting actors and on the role of interdepend and interacting institutions in value practices.