Projects promise to coordinate innovative activities without sacrificing efficiency. However, for a long time, conventional project management has emphasized control over creativity and, only in the last decades, explicitly focused on the issue of innovation, including radical innovation. Going beyond management, sociological research shows that projects do not always ensure efficient planning but instead have other functions and effects: They can legitimize creative and risky activities, increase opportunities for reflection when deadlines and milestones are not met, and buffer innovative work against interference from other organizational activities and internal or external demands. In addition, there is a growing interest in analyzing the relationship between temporary project structures and permanent intra- and interorganizational structures. This line of research investigates, on the one hand, how permanent structural elements facilitate the production of novelties in projects and, on the other hand, which structural arrangements of organizations, networks, or social fields positively influence the diffusion of innovation, allowing novelties to spread beyond project boundaries.