There are many approaches to understanding value cocreation embedded in a service ecosystem. Usually, the value cocreation has portrayed “ecosystem as a structure.” In this chapter, the authors emphasize the ecosystem “as an agency,” focusing on the actor’s essential role. The ecosystem lens has developed with the key concepts of actors’ resources and institutional arrangements, shaping value cocreation. Some authors have defined “service ecosystems” as relatively self-contained, self-adjusting systems of resource-integrating actors connected by shared institutional arrangements and mutual value creation through service exchange. Accordingly, value cocreation in service ecosystems is “coordinated through actor-generated institutions and institutional arrangements.” However, the authors argue that the key role of actors, their collaboration, and the orchestration of research in value cocreation processes is still underdeveloped and needs more attention. Agency-structure theories should then discuss the actor’s key role for value cocreation by looking at both societal- and individual-focused realms, thus including social aspects of service ecosystems. Next, the chapter offers a brief review of the service ecosystem literature and discusses the key role of collaborating actors in service ecosystems; finally, it provides suggestions for future service research grounded in a service ecosystem view on value cocreation.