More Americans now play video games than go to the movies (NPD Group, 2009). The meteoric rise in popularity of video games highlights the need for research approaches that can deepen our scientific understanding of video game engagement. This article advances a theory-based motivational model for examining and evaluating the ways by which video game engagement shapes psychological processes and influences well-being. Rooted in self-determination theory (Deci & Ryan, 2000;Ryan & Deci, 2000a), our approach suggests that both the appeal and well-being effects of video games are based in their potential to satisfy basic psychological needs for competence, autonomy, and relatedness. We review recent empirical evidence applying this perspective to a number of topics including need satisfaction in games and short-term well-being, the motivational appeal of violent game content, motivational sources of postplay aggression, the antecedents and consequences of disordered patterns of game engagement, and the determinants and effects of immersion. Implications of this model for the future study of game motivation and the use of video games in interventions are discussed.Keywords: self-determination theory, motivation, video games Psychological research examining video games is presently undergoing a dramatic shift in focus. Until very recently, the preponderance of research in video games has been concern-focused, with studies aimed at identifying the potential negative effects of gaming. Specific foci of these research programs have included the relations between gaming and increased aggression, social isolation, and overuse (Anderson & Bushman, 2001;Grüsser, Thalemann, & Griffiths, 2007). Yet, more recently, a number of researchers have become intervention-focused, hoping to harness the magnetic motivational appeal of video games to help relieve pain and stress or customizing games for educational or health-related interventions (for a review, see Baranowski, Buday, Thompson, & Baranowski, 2008). Increasingly, intervention-focused researchers are demonstrating that games can positively influence both psychological and physical well-being.Although the goals of both concern-focused and interventionfocused research are dissimilar, both share a descriptive research approach: The methods and theories they employ evaluate the extent to which video games exert positive, negative, or no influence on specified outcomes under a given set of circumstances. What is less well understood and less widely studied are the mechanisms that underlie these positive and negative links.In this article, we outline a theory-based empirical model for understanding and evaluating the processes through which video games motivate sustained engagement, and how experiences with these games affect the psychological and physical well-being of players. Our approach is based on self-determination theory (SDT; Deci & Ryan, 2000;Ryan & Deci, 2000a), a macrotheory of human motivation that is principally concerned with the potential of social contexts to prov...