Identity is crucial to social movement participation. Existing research examines why active people “avoid” activist identities but has less to say about how active people adopt such identities as if they automatically follow participation. We draw on interviews with high school and college students from a midsize southwestern city to examine how young people make sense of what it means to be an activist, who identifies as such, and why youth are willing—or unwilling—to adopt this label. We find that respondents' conceptualizations of “activists” are critical to (non)identification. Those who see activism as a broad category are more likely to identify, holding constant their level of activity. Those who see activism as a greedy institution, requiring significant substantive fluency, making the issue their primary focus, and willingness to sacrifice, do not, despite their level of engagement. Our findings have implications for identity formation and movement participation more broadly.