Purpose of Review: The playing of videogames has become an everyday occurrence among many adolescents and emerging adults. However, gaming can be problematic and potentially addictive and problematic gamers can experience co-occurring behavioral or substance use-related problems. The aims of the present review were to (i) determine the co-occurrence of potentially addictive behaviors with problematic and disordered gaming, and (ii) elucidate the potential risk factors in the development and maintenance of co-occurrence within disordered gaming. Recent Findings: The main findings demonstrated that there are few empirical studies (N = 20) examining (i) co-occurrence of gaming disorder with other addictive behaviors; (ii) longitudinal risk of disordered gaming with co-occurring addictive behaviors; and (iii) mechanisms of co-occurrence in disordered gaming with co-occurring potentially addictive behaviors. Results suggest that disordered gaming can co-occur with a variety of other addictive behaviors (e.g., alcohol use disorder or addictive use of social media), and that research into the co-occurrence of addictive behaviors and substance use is increasing. Summary: Based on this systematic review, findings suggest that gamers engage in a number of potentially addictive behaviors and substance use which can have detrimental effects on health and wellbeing. While a majority of the reviewed studies consider prevalence rates from a range of geographical locations, there are fewer papers which investigate individual and environmental risk factors.