This study examines the peer relations and emotion practices of adolescent boys in light of their expectations and assumptions about masculinity. We carried out semistructured interviews with middle-class and upper-middle-class boys from an independent high school. The boys reported that they assiduously avoided displays of emotional or physical pain and disparaged such displays in other boys. They tied tough, stoic self-presentations to manliness; moreover, they said that their peer groups derided expressions of hurt and worry and of care and concern for others as "gay" or "girly." Boys described interactions with boys as centering on taunting, mocking, and "shoving around." Although these practices were hurtful, boys valued them as means of bolstering one another's masculinity. The study points out that securing masculinity demands ongoing efforts from boys and their peers. Moreover, it points to feeling rules and emotion practices as important constituents of young White masculinities.