Affective gaming has received much attention lately, as the gaming community recognizes the importance of emotion in the development of engaging games. Affect plays a key role in the user experience, both in entertainment and in ‘serious’ games. Current focus in affective gaming is primarily on the sensing and recognition of the players’ emotions, and on tailoring the game responses to these emotions. A significant effort is also being devoted to generating ‘affective behaviors’ in the game characters, and in player avatars, to enhance their realism and believability. Less emphasis is placed on modeling emotions, both their generation and their effects, in the game characters, and in user models representing the players. This paper discusses how the emerging discipline of affective computing contributes to each of these three elements of affective game design, with emphasis on the importance of affective modeling. The paper provides a summary of a conference tutorial whose aim is to enable game designers to make informed choices about where to incorporate emotion in games, and provide information about existing data and theories from the affective sciences, and relevant methods and techniques from affective computing, to support affect-focused game design.