This legal issue brief focuses on “viral” or “word-of-mouth” marketing. Viral marketing campaigns are designed to mask their commercial origin, which raises multiple issues related to protecting consumers, especially young children. These campaigns are used to drive traffic to a firm’s website, Facebook page, or online marketing application. The brief describes viral marketing tactics used by firms; how firms derive value from these tactics; privacy concerns about these tactics aimed at young children and the personal information children may share, often without the knowledge or consent of parents; and how viral marketing tactics may violate state Unfair and Deceptive Acts and Practices (UDAP) statutes.