Most of the research on public perceptions of people with addictive disorders has focused on alcohol and illicit drugs, rather than addiction to behavioral activities. To expand the range of addictive behaviors and types of perceptions studied, we designed the present study to assess the lay public’s definitions of and willingness to affiliate with people described as addicted to 1 of 2 specific behaviors (i.e., pornography or gambling) or 1 of 3 specific substances (i.e., alcohol, marijuana, or heroin). A nationwide convenience sample (N = 612) of American adults completed online questionnaires during the summer of 2015. Participants rated heroin as more addictive than the other drugs and behaviors and, despite differences among the conditions, were generally unwilling to affiliate with an individual addicted to any of the 2 behaviors or 3 substances. When asked to rate different potential indications of addiction, participants endorsed behavioral signs of impaired control and physiological and psychological dependence as more indicative of all 5 types of addiction than desire to use the substance or engage in the addictive behavior. Despite recent efforts to increase public knowledge about addictive disorders, members of the public continue to endorse some attitudes indicative of stigmatization toward people with selected substance and behavioral addictions.