This chapter serves as the introduction to 21 st Century Media and Female Mental Health: Profitable Vulnerability and Sad Girl Culture. As such it describes the prevalence of sadness and mental health awareness in the popular media landscape of the 2020s. I describe the main sites studied—magazines, celebrities, and social media networks—to understand the contemporary discourse around gendered mental health, and the feminist media studies theories I use in my analysis. The chapter also contains a timeline of the emergence of a twenty-first-century sadness, exemplified by the artist Lana del Rey and her employment of a sad aesthetics. I also define my use of the terms neoliberalism, governmentality, biopolitics, postfeminism, and popular feminism, before briefly accounting for feminist approaches to affect theory. The chapter ends with an outline of the other chapters in the book.