Should excessive and problematic engagement in non-substance use behaviors be mental disorders? The fifth revision of the Diagnostic and Statistical Manual for Mental Disorders (DSM-5) repositioned gambling disorder in the substance use disorders section and introduced Internet gaming disorder in the research appendix; the International Classification of Diseases (ICD-11) is also considering it. This article outlines pros and cons of considering “behavioral addictions” as mental disorders and the DSM-5 decision making processes. It focuses upon three conditions: gambling disorder, Internet gaming disorder, and Internet addiction. The paper details assessment methods and prevalence rates for these conditions and outlines psychiatric comorbidities, demographic and biological risk factors, and promising treatment approaches. The paper also briefly discusses other putative behavioral addictions: eating/food, sex, exercise, shopping, and tanning “addictions.” Overall, data are inconclusive, and consistent terminology and methodology are needed to define and evaluate these conditions more fully prior to considering them mental disorders.