No longer is service design a playground for pretty storyboards – it has become an essential driver for innovation and creator of value for relevant stakeholders. And this value is created through implementation. Still: brilliant concepts often fail when it comes to implementation. Finding answers and better understanding the complex drivers for implementation, barriers and success factors was the motivation behind a 3-year international study. The talk will present the key findings of this study, which investigated complex service design projects at the interface of external SD consultancies and their clients.