Digital platforms are often characterized as enablers of new ecosystems. However, platforms are sometimes introduced into pre-existing ecosystems, where a platform's ability to harmonize with the ecosystem is critical for its success. This article draws on the case of digital healthcare platforms and introduces the concept of platform grafting, which denotes the process of integrating a new platform into a pre-existing ecosystem, leading to a coevolutionary process of adapting both the platform and the surrounding ecosystem. Dynamic capabilities are critical for successfully integrating the platform into the ecosystem, and this article provides a capabilities framework for understanding platform grafting.

Four years of research by a team in Sweden uncovered the unique challenges emerging digital health platforms face, such as integrating with existing solutions in a largely physical health care system and exerting influence in a tightly regulated industry. Based on more than 100 interviews with leaders and managers at 14 organizations in Sweden, the researchers developed a three-part strategy to help digital health platforms successfully scale to address global health care systems challenges.

Open innovation rests on the idea that not all the smart people work only for you, and managing human interaction across organizational boundaries is therefore central to open innovation. This article starts with outlining and reviewing research on this human dimension of open innovation. The article develops seven principles of innovation- producing encounters that can guide managers in enabling value creation through open innovation. We continue by introducing the rest of the special section, which expands beyond the human dimension to also include firms, platforms, and ecosystems, with important implications for the creation and capture of value from open innovation.

Ecosystems are the result of a delicate balance between centripetal forces that push economic activities toward integration, and centrifugal forces that pull economic activities out onto the market. Ecosystems evolve when these forces change. For example, technological complementarities - the main source of centripetal force - are dynamic and may be commoditized, generalized, or standardized over time. Management and coordination also change: for example, open innovation practices enable firms to move innovation activities from the in-house R&D lab out into the ecosystem. This article discusses how such dynamics in technologies and management lead to ecosystem evolution.

Open innovation includes external knowledge sources and paths to market as complements to internal innovation processes. Open innovation has to date been driven largely by business objectives, but the imperative of social challenges has turned attention to the broader set of goals to which open innovation is relevant. This introduction discusses how open innovation can be deployed to address societal challenges - as well as the trade-offs and tensions that arise as a result. Against this background we introduce the articles published in this Special Section, which were originally presented at the sixth Annual World Open Innovation Conference.