Social media have been (for quite some time now) part of the fabric of our lives. But as with many new technologies, it often takes a while for us to be able to step back, assess the tool's impact, and consider what's next. This collection offers one of the first sets of scholarly work in our field that responds to social media's influence on both popular and extra-curricular writing as well as on scholarly communication. Too frequently, social media is dismissed as non-academic, unworthy of sustained attention by researchers. The authors featured here present compelling reasons why this oft-neglected form of writing deserves—and demands—continued academic response. Social Writing/Social Media: Publics, Presentations, and Pedagogies makes this contribution by examining the impact of social media on three writing-related themes: publics and audiences, presentation of self and groups, and pedagogy at various levels of higher education. The contributors to this collection urge readers to pay attention to an undertheorized aspect of writing online—the acts of composing that occur specifically in social-media spaces. Organized in three sections—social media and public audiences; social media and presentation; and social media and pedagogy—it builds on previous explorations of the role of multimodality in composition studies by extending ongoing conversations that have asked readers to expand notions of literacy in the twenty-first century. By addressing the wide range of composing activities that take place in social media and the rich variety of genres, audiences, stylistic choices, and pedagogical possibilities, this collection offers an important contribution to our understanding of pedagogy and practice in social media spaces.