The purpose of this paper is to investigate the ethical implications of video game companies employing psychologists and using psychological research in game design.,The author first argues that exploiting psychology in video games may be more ethically problematic than familiar application domains like advertising, gambling and political rhetoric. Then an overview of the effects particular types of game design may have on user behavior is provided, taking into account various findings and phenomena from behavioral psychology and behavioral economics.,Finally, the author (...) concludes that the corresponding ethical problems cannot – and should not – be addressed by means of regulation or rating systems. The author argues instead that a more promising countermeasure lies in using the same psychological research to educate gamers (children in particular) and thereby increase their capacity for meta-cognition.,The importance of this lies in the tremendous effect these behavior-modifying technologies may have upon our self-determination, well-being and social relations, as well as corresponding implications for the society. (shrink)