In this paper, we present Greenolive, an open platform for wellness management ecosystem. Wellness management applications, which facilitate preventive care and chronic disease treatments, are considered as a key component to enhance healthcare quality and reduce healthcare cost. Currently, most of the wellness management applications are device-oriented, stand-alone software and lack of open APIs that allow new value-added applications to be developed rapidly. Further, these wellness applications have not fully utilized the collected wellness monitoring data to generate new knowledge that can help people to further improve their wellness status. In this paper, we advocate an open platform that provides services that are essential to wellness management, and manages the services to be developed. Further, we adopt an elastic infrastructure to deal with scalability issues. We expect independent software vendors to develop new wellness management applications using the provided services and to deploy them on the platform. We believe such an ecosystem can greatly promote wellness management applications, much like we witness in other application domains, e.g., social network, enterprise resource management. © 2010 IEEE.