Adolescents in the United States today can choose from a variety of social media platforms, which afford varying degrees of anonymity, allowing users to engage in anonymous, pseudonymous, or "real name" interactions in order to meet social or informational goals. Although many social media platforms are "profile-centric" and include an emphasis on the profile of a specific user and his or her actions (Ellison & boyd, 2013), others specifically encourage anonymous (e.g., Yik Yak) or pseudonymous (e.g., Reddit) interactions. Despite known benefits associated with varying degrees of identifiability, few platforms enable users to choose between multiple forms of identity expression using a single account. In this article, we use semi-structured interview data collected from US adolescents aged 13-18 years (N = 22) to explore adolescents' use of selective anonymity on an online platform that allows for both anonymous and pseudonymous interaction. We contribute to scholarship on mediated anonymous interaction by explicating the reasons why young adults might choose to interact in contexts that do not contribute to their overall social media presence (e.g., their "real name" or persistently identifiable accounts) by examining adolescents' social practices on Ask.fm, a question-and-answer (Q&A) site popular with teenagers, and the outcomes they associate with its use. Adolescents' use of anonymous interaction is an important topic of study given the developmental processes associated with this stage of life, the high rates of social media use among this population, and the affordances of social media sites that shape the social and psychological outcomes of their use. Prior literature associates anonymity with both positive and negative outcomes. For instance, anonymous and pseudonymous platforms are often linked with disinhibited behaviors (Suler, 2004), which can include abuse and harassment (Cho & Acquisti, 2013; Diakopoulos & Naaman, 2011). However, because people 670673S MSXXX10.1177/2056305116670673Social Media + SocietyEllison et al.