As a backlash against capitalism, there is a growing resistance to transnational brands and corporate globalization. One form of this resistance is the emergence of anti-brand communities on the Internet. The purpose of this study was to understand the nature of online anti-brand communities as a form of social action. The inquiry was guided by the following research questions: Why do online anti-brand communities form? What action strategies do online anti-brand communities engage in and how does the Internet shape those activities? How does learning occur in online anti-brand communities? A comparative qualitative case study design was employed to address the purpose of the study. Three online anti-brand community cases were examined: anti-Starbucks, anti-Wal-Mart, and anti-McDonalds. Data collection consisted of a total of 15 in-depth interviews, printouts of web-based discussions, and website documents (i.e., newsletters, updates, announcements). Using the constant comparative method of data analysis, individual case and cross-case analyses were conducted. Descriptive data were used to establish common traits or themes within each case. For cross-case analysis, data from each individual case was compared with the other cases to identify common themes across cases. Data analysis revealed four distinct reasons why anti-brand communities form: 1) in response to a common sense of moral responsibility, 2) to provide a support group to achieve common goals, 3) in response to workplace difficulties, and 4) to provide resources for taking action. Anti-brand communities engage in two types of action strategies: online (e.g., online petitions, coordinated email campaigns, monetary donations) and offline (e.g., resistance in the workplace, forming local groups, onsite protests, boycotting). Findings suggest the Internet radically affects social action strategies in five major ways: 1) speed, 2) convenience, 3) nature of community formation, 4) anonymity, and 5) widespread viewership. Learning occurs within these online communities through observations/exposure, story-telling, and dialogue and discussion. Based on the findings of the study, three conclusions are presented. First, online anti-stbrand communities represent one form of social action for the 21 Century. Second, the online medium is able to maximize potential for social action strategies. Third, online anti-brand communities are important sites for learning.