Despite scant empirical substantiation, serious games are in widespread use. The authors review 28 studies with empirical data from a learning outcome perspective to outline the effectiveness of serious games (compared to other learning approaches and specific game features). They conclude that serious games potentially improve the acquisition of knowledge and cognitive skills. Moreover, they seem to be promising for the acquisition of fine-grid motor skills and to accomplish attitudinal change. However, not all game features increase the effectiveness of the game. To further advance game research the chapter proposes recommendations including the alignment of learning outcome(s) and game type, the alignment of the game complexity and human cognitive processes, attention for cognitive and motivational processes, research on specific mitigating factors like gender on game effectiveness and, finally, developing new ways of assessing game effectiveness. (http://www.cs.uu.nl/docs/vakken/b3elg/literatuur_files/Wouters.pdf)
