In this paper we will discuss how positive psychology can contribute to the design of digital games and in particular training applications like Serious Games. While digital games have been known for their ability to deeply immerse users, stimulate the senses and tap into a broad range of emotions, it has proven rather challenging to use them as a vehicle for pedagogy. Relevant research is still at its infancy and many of the mechanisms that foster knowledge creation and enhance learning need to be mapped out before scripted in the game. The theory of psychological flow and the role of positive emotions in broadening people’s thought-action repertoires bring some practical insights and pave the path for tackling some important design questions. Yet there are still major challenges and uncharted waters to be explored in order for the technology to deliver what has been promised.