Playing online games can become problematic and engender adverse consequences. Several psychological factors have been shown to influence the development and the maintenance of this problematic behavior, including impulsivity traits, motives to play (immersion, achievement, social affiliation), and self-esteem. The aim of the current study is to determine whether reliable subtypes of problematic online gamers can be identified. A sample of 1057 online gamers was recruited. Validated questionnaires were used to measure established psychological risk factors (impulsivity, motives to play, self-esteem) and potential consequences of playing (addiction symptoms, positive and negative affect). Actual in-game behaviors were also monitored. Five reliable clusters of gamers were identified (three problematic and two nonproblematic clusters). Cluster comparison revealed that the psychological factors considered are differentially involved in problematic online gaming. At the theoretical level, the results emphasized that problem online gaming depends on a wide range of psychological factors. At the clinical level, the diversity of psychological profiles shown supports the development of personalized (custom-made) interventions targeting specific psychological mechanisms. Overall, our findings suggest that conceptualizing the problematic use of massively multiplayer online role-playing games as ‘‘behavioral addiction'' is too restrictive and might result in the simplification of heterogeneous and multi-determined problematic behaviors. cop. 2014 Elsevier Ltd. All Rights reserved.